diff --git a/src/backend/worksheet/plots/cartesian/CartesianPlot.cpp b/src/backend/worksheet/plots/cartesian/CartesianPlot.cpp
index b54822e98..07cffc5fd 100644
--- a/src/backend/worksheet/plots/cartesian/CartesianPlot.cpp
+++ b/src/backend/worksheet/plots/cartesian/CartesianPlot.cpp
@@ -1,3168 +1,3167 @@
 /***************************************************************************
     File                 : CartesianPlot.cpp
     Project              : LabPlot
     Description          : Cartesian plot
     --------------------------------------------------------------------
     Copyright            : (C) 2011-2018 by Alexander Semke (alexander.semke@web.de)
     Copyright            : (C) 2016-2018 by Stefan Gerlach (stefan.gerlach@uni.kn)
     Copyright            : (C) 2017-2018 by Garvit Khatri (garvitdelhi@gmail.com)
 
  ***************************************************************************/
 
 /***************************************************************************
  *                                                                         *
  *  This program is free software; you can redistribute it and/or modify   *
  *  it under the terms of the GNU General Public License as published by   *
  *  the Free Software Foundation; either version 2 of the License, or      *
  *  (at your option) any later version.                                    *
  *                                                                         *
  *  This program is distributed in the hope that it will be useful,        *
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of         *
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the          *
  *  GNU General Public License for more details.                           *
  *                                                                         *
  *   You should have received a copy of the GNU General Public License     *
  *   along with this program; if not, write to the Free Software           *
  *   Foundation, Inc., 51 Franklin Street, Fifth Floor,                    *
  *   Boston, MA  02110-1301  USA                                           *
  *                                                                         *
  ***************************************************************************/
 
 #include "CartesianPlot.h"
 #include "CartesianPlotPrivate.h"
 #include "Axis.h"
 #include "XYCurve.h"
 #include "Histogram.h"
 #include "XYEquationCurve.h"
 #include "XYDataReductionCurve.h"
 #include "XYDifferentiationCurve.h"
 #include "XYIntegrationCurve.h"
 #include "XYInterpolationCurve.h"
 #include "XYSmoothCurve.h"
 #include "XYFitCurve.h"
 #include "XYFourierFilterCurve.h"
 #include "XYFourierTransformCurve.h"
 #include "XYConvolutionCurve.h"
 #include "XYCorrelationCurve.h"
 #include "backend/core/Project.h"
 #include "backend/core/datatypes/DateTime2StringFilter.h"
 #include "backend/spreadsheet/Spreadsheet.h"
 #include "backend/worksheet/plots/cartesian/CartesianPlotLegend.h"
 #include "backend/worksheet/plots/cartesian/CustomPoint.h"
 #include "backend/worksheet/plots/PlotArea.h"
 #include "backend/worksheet/plots/AbstractPlotPrivate.h"
 #include "backend/worksheet/Worksheet.h"
 #include "backend/worksheet/plots/cartesian/Axis.h"
 #include "backend/worksheet/TextLabel.h"
 #include "backend/lib/XmlStreamReader.h"
 #include "backend/lib/commandtemplates.h"
 #include "backend/lib/macros.h"
 #include "backend/lib/trace.h"
 #include "kdefrontend/spreadsheet/PlotDataDialog.h" //for PlotDataDialog::AnalysisAction. TODO: find a better place for this enum.
 #include "kdefrontend/ThemeHandler.h"
 #include "kdefrontend/widgets/ThemesWidget.h"
 
 #include <QDir>
 #include <QDropEvent>
 #include <QIcon>
 #include <QMenu>
 #include <QMimeData>
 #include <QPainter>
-#include <QToolBar>
 #include <QWidgetAction>
 
 #include <KConfig>
 #include <KConfigGroup>
 #include <KLocalizedString>
 
 /**
  * \class CartesianPlot
  * \brief A xy-plot.
  *
  *
  */
 CartesianPlot::CartesianPlot(const QString &name) : AbstractPlot(name, new CartesianPlotPrivate(this)) {
 	init();
 }
 
 CartesianPlot::CartesianPlot(const QString &name, CartesianPlotPrivate *dd) : AbstractPlot(name, dd) {
 	init();
 }
 
 CartesianPlot::~CartesianPlot() {
 	if (m_menusInitialized) {
 		delete addNewMenu;
 		delete zoomMenu;
 		delete themeMenu;
 	}
 
 	delete m_coordinateSystem;
 
 	//don't need to delete objects added with addChild()
 
 	//no need to delete the d-pointer here - it inherits from QGraphicsItem
 	//and is deleted during the cleanup in QGraphicsScene
 }
 
 /*!
 	initializes all member variables of \c CartesianPlot
 */
 void CartesianPlot::init() {
 	Q_D(CartesianPlot);
 
 	d->cSystem = new CartesianCoordinateSystem(this);
 	m_coordinateSystem = d->cSystem;
 
 	d->rangeType = CartesianPlot::RangeFree;
 	d->xRangeFormat = CartesianPlot::Numeric;
 	d->yRangeFormat = CartesianPlot::Numeric;
 	d->xRangeDateTimeFormat = "yyyy-MM-dd hh:mm:ss";
 	d->yRangeDateTimeFormat = "yyyy-MM-dd hh:mm:ss";
 	d->rangeFirstValues = 1000;
 	d->rangeLastValues = 1000;
 	d->autoScaleX = true;
 	d->autoScaleY = true;
 	d->xScale = ScaleLinear;
 	d->yScale = ScaleLinear;
 	d->xRangeBreakingEnabled = false;
 	d->yRangeBreakingEnabled = false;
 
 	//the following factor determines the size of the offset between the min/max points of the curves
 	//and the coordinate system ranges, when doing auto scaling
 	//Factor 0 corresponds to the exact match - min/max values of the curves correspond to the start/end values of the ranges.
 	//TODO: make this factor optional.
 	//Provide in the UI the possibility to choose between "exact" or 0% offset, 2%, 5% and 10% for the auto fit option
 	d->autoScaleOffsetFactor = 0.0f;
 
 	m_plotArea = new PlotArea(name() + " plot area");
 	addChildFast(m_plotArea);
 
 	//Plot title
 	m_title = new TextLabel(this->name() + QLatin1String("- ") + i18n("Title"), TextLabel::PlotTitle);
 	addChild(m_title);
 	m_title->setHidden(true);
 	m_title->setParentGraphicsItem(m_plotArea->graphicsItem());
 
 	//offset between the plot area and the area defining the coordinate system, in scene units.
 	d->horizontalPadding = Worksheet::convertToSceneUnits(1.5, Worksheet::Centimeter);
 	d->verticalPadding = Worksheet::convertToSceneUnits(1.5, Worksheet::Centimeter);
 
 	connect(this, SIGNAL(aspectAdded(const AbstractAspect*)), this, SLOT(childAdded(const AbstractAspect*)));
 	connect(this, SIGNAL(aspectRemoved(const AbstractAspect*,const AbstractAspect*,const AbstractAspect*)),
 	        this, SLOT(childRemoved(const AbstractAspect*,const AbstractAspect*,const AbstractAspect*)));
 
 	graphicsItem()->setFlag(QGraphicsItem::ItemIsMovable, true);
 	graphicsItem()->setFlag(QGraphicsItem::ItemClipsChildrenToShape, true);
 	graphicsItem()->setFlag(QGraphicsItem::ItemIsSelectable, true);
 	graphicsItem()->setFlag(QGraphicsItem::ItemSendsGeometryChanges, true);
 	graphicsItem()->setFlag(QGraphicsItem::ItemIsFocusable, true);
 }
 
 /*!
 	initializes all children of \c CartesianPlot and
 	setups a default plot of type \c type with a plot title.
 */
 void CartesianPlot::initDefault(Type type) {
 	Q_D(CartesianPlot);
 
 	switch (type) {
 	case FourAxes: {
 			d->xMin = 0.0;
 			d->xMax = 1.0;
 			d->yMin = 0.0;
 			d->yMax = 1.0;
 
 			//Axes
 			Axis* axis = new Axis("x axis 1", Axis::AxisHorizontal);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisBottom);
 			axis->setStart(0);
 			axis->setEnd(1);
 			axis->setMajorTicksDirection(Axis::ticksIn);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksIn);
 			axis->setMinorTicksNumber(1);
 			QPen pen = axis->majorGridPen();
 			pen.setStyle(Qt::SolidLine);
 			axis->setMajorGridPen(pen);
 			pen = axis->minorGridPen();
 			pen.setStyle(Qt::DotLine);
 			axis->setMinorGridPen(pen);
 			axis->setSuppressRetransform(false);
 
 			axis = new Axis("x axis 2", Axis::AxisHorizontal);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisTop);
 			axis->setStart(0);
 			axis->setEnd(1);
 			axis->setMajorTicksDirection(Axis::ticksIn);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksIn);
 			axis->setMinorTicksNumber(1);
 			pen = axis->minorGridPen();
 			pen.setStyle(Qt::NoPen);
 			axis->setMajorGridPen(pen);
 			pen = axis->minorGridPen();
 			pen.setStyle(Qt::NoPen);
 			axis->setMinorGridPen(pen);
 			axis->setLabelsPosition(Axis::NoLabels);
 			axis->title()->setText(QString());
 			axis->setSuppressRetransform(false);
 
 			axis = new Axis("y axis 1", Axis::AxisVertical);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisLeft);
 			axis->setStart(0);
 			axis->setEnd(1);
 			axis->setMajorTicksDirection(Axis::ticksIn);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksIn);
 			axis->setMinorTicksNumber(1);
 			pen = axis->majorGridPen();
 			pen.setStyle(Qt::SolidLine);
 			axis->setMajorGridPen(pen);
 			pen = axis->minorGridPen();
 			pen.setStyle(Qt::DotLine);
 			axis->setMinorGridPen(pen);
 			axis->setSuppressRetransform(false);
 
 			axis = new Axis("y axis 2", Axis::AxisVertical);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisRight);
 			axis->setStart(0);
 			axis->setEnd(1);
 			axis->setOffset(1);
 			axis->setMajorTicksDirection(Axis::ticksIn);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksIn);
 			axis->setMinorTicksNumber(1);
 			pen = axis->minorGridPen();
 			pen.setStyle(Qt::NoPen);
 			axis->setMajorGridPen(pen);
 			pen = axis->minorGridPen();
 			pen.setStyle(Qt::NoPen);
 			axis->setLabelsPosition(Axis::NoLabels);
 			axis->title()->setText(QString());
 			axis->setSuppressRetransform(false);
 
 			break;
 		}
 	case TwoAxes: {
 			d->xMin = 0.0;
 			d->xMax = 1.0;
 			d->yMin = 0.0;
 			d->yMax = 1.0;
 
 			Axis* axis = new Axis("x axis 1", Axis::AxisHorizontal);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisBottom);
 			axis->setStart(0);
 			axis->setEnd(1);
 			axis->setMajorTicksDirection(Axis::ticksBoth);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksBoth);
 			axis->setMinorTicksNumber(1);
 			axis->setArrowType(Axis::FilledArrowSmall);
 			axis->setSuppressRetransform(false);
 
 			axis = new Axis("y axis 1", Axis::AxisVertical);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisLeft);
 			axis->setStart(0);
 			axis->setEnd(1);
 			axis->setMajorTicksDirection(Axis::ticksBoth);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksBoth);
 			axis->setMinorTicksNumber(1);
 			axis->setArrowType(Axis::FilledArrowSmall);
 			axis->setSuppressRetransform(false);
 
 			break;
 		}
 	case TwoAxesCentered: {
 			d->xMin = -0.5;
 			d->xMax = 0.5;
 			d->yMin = -0.5;
 			d->yMax = 0.5;
 
 			d->horizontalPadding = Worksheet::convertToSceneUnits(1.0, Worksheet::Centimeter);
 			d->verticalPadding = Worksheet::convertToSceneUnits(1.0, Worksheet::Centimeter);
 
 			QPen pen = m_plotArea->borderPen();
 			pen.setStyle(Qt::NoPen);
 			m_plotArea->setBorderPen(pen);
 
 			Axis* axis = new Axis("x axis 1", Axis::AxisHorizontal);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisCentered);
 			axis->setStart(-0.5);
 			axis->setEnd(0.5);
 			axis->setMajorTicksDirection(Axis::ticksBoth);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksBoth);
 			axis->setMinorTicksNumber(1);
 			axis->setArrowType(Axis::FilledArrowSmall);
 			axis->title()->setText(QString());
 			axis->setSuppressRetransform(false);
 
 			axis = new Axis("y axis 1", Axis::AxisVertical);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisCentered);
 			axis->setStart(-0.5);
 			axis->setEnd(0.5);
 			axis->setMajorTicksDirection(Axis::ticksBoth);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksBoth);
 			axis->setMinorTicksNumber(1);
 			axis->setArrowType(Axis::FilledArrowSmall);
 			axis->title()->setText(QString());
 			axis->setSuppressRetransform(false);
 
 			break;
 		}
 	case TwoAxesCenteredZero: {
 			d->xMin = -0.5;
 			d->xMax = 0.5;
 			d->yMin = -0.5;
 			d->yMax = 0.5;
 
 			d->horizontalPadding = Worksheet::convertToSceneUnits(1.0, Worksheet::Centimeter);
 			d->verticalPadding = Worksheet::convertToSceneUnits(1.0, Worksheet::Centimeter);
 
 			QPen pen = m_plotArea->borderPen();
 			pen.setStyle(Qt::NoPen);
 			m_plotArea->setBorderPen(pen);
 
 			Axis* axis = new Axis("x axis 1", Axis::AxisHorizontal);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisCustom);
 			axis->setOffset(0);
 			axis->setStart(-0.5);
 			axis->setEnd(0.5);
 			axis->setMajorTicksDirection(Axis::ticksBoth);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksBoth);
 			axis->setMinorTicksNumber(1);
 			axis->setArrowType(Axis::FilledArrowSmall);
 			axis->title()->setText(QString());
 			axis->setSuppressRetransform(false);
 
 			axis = new Axis("y axis 1", Axis::AxisVertical);
 			axis->setSuppressRetransform(true);
 			addChild(axis);
 			axis->setPosition(Axis::AxisCustom);
 			axis->setOffset(0);
 			axis->setStart(-0.5);
 			axis->setEnd(0.5);
 			axis->setMajorTicksDirection(Axis::ticksBoth);
 			axis->setMajorTicksNumber(6);
 			axis->setMinorTicksDirection(Axis::ticksBoth);
 			axis->setMinorTicksNumber(1);
 			axis->setArrowType(Axis::FilledArrowSmall);
 			axis->title()->setText(QString());
 			axis->setSuppressRetransform(false);
 
 			break;
 		}
 	}
 
 	d->xMinPrev = d->xMin;
 	d->xMaxPrev = d->xMax;
 	d->yMinPrev = d->yMin;
 	d->yMaxPrev = d->yMax;
 
 	//Geometry, specify the plot rect in scene coordinates.
 	//TODO: Use default settings for left, top, width, height and for min/max for the coordinate system
 	float x = Worksheet::convertToSceneUnits(2, Worksheet::Centimeter);
 	float y = Worksheet::convertToSceneUnits(2, Worksheet::Centimeter);
 	float w = Worksheet::convertToSceneUnits(10, Worksheet::Centimeter);
 	float h = Worksheet::convertToSceneUnits(10, Worksheet::Centimeter);
 
 	//all plot children are initialized -> set the geometry of the plot in scene coordinates.
 	d->rect = QRectF(x,y,w,h);
 }
 
 void CartesianPlot::initActions() {
 	//"add new" actions
 	addCurveAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("xy-curve"), this);
 	addHistogramAction = new QAction(QIcon::fromTheme("view-object-histogram-linear"), i18n("Histogram"), this);
 	addEquationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-equation-curve"), i18n("xy-curve from a mathematical Equation"), this);
 // no icons yet
 	addDataReductionCurveAction = new QAction(i18n("xy-curve from a Data Reduction"), this);
 	addDifferentiationCurveAction = new QAction(i18n("xy-curve from a Differentiation"), this);
 	addIntegrationCurveAction = new QAction(i18n("xy-curve from an Integration"), this);
 	addInterpolationCurveAction = new QAction(i18n("xy-curve from an Interpolation"), this);
 	addSmoothCurveAction = new QAction(i18n("xy-curve from a Smooth"), this);
 	addFitCurveAction = new QAction(QIcon::fromTheme("labplot-xy-fit-curve"), i18n("xy-curve from a Fit to Data"), this);
 	addFourierFilterCurveAction = new QAction(i18n("xy-curve from a Fourier Filter"), this);
 	addFourierTransformCurveAction = new QAction(i18n("xy-curve from a Fourier Transform"), this);
 	addConvolutionCurveAction = new QAction(i18n("xy-curve from a (De-)Convolution"), this);
 	addCorrelationCurveAction = new QAction(i18n("xy-curve from a Correlation"), this);
 //	addInterpolationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-interpolation-curve"), i18n("xy-curve from an interpolation"), this);
 //	addSmoothCurveAction = new QAction(QIcon::fromTheme("labplot-xy-smooth-curve"), i18n("xy-curve from a smooth"), this);
 //	addFourierFilterCurveAction = new QAction(QIcon::fromTheme("labplot-xy-fourier_filter-curve"), i18n("xy-curve from a Fourier filter"), this);
 //	addFourierTransformCurveAction = new QAction(QIcon::fromTheme("labplot-xy-fourier_transform-curve"), i18n("xy-curve from a Fourier transform"), this);
 //	addConvolutionCurveAction = new QAction(QIcon::fromTheme("labplot-xy-convolution-curve"), i18n("xy-curve from a (de-)convolution"), this);
 //	addCorrelationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-correlation-curve"), i18n("xy-curve from a correlation"), this);
 	addLegendAction = new QAction(QIcon::fromTheme("text-field"), i18n("Legend"), this);
 	if (children<CartesianPlotLegend>().size()>0)
 		addLegendAction->setEnabled(false);	//only one legend is allowed -> disable the action
 
 	addHorizontalAxisAction = new QAction(QIcon::fromTheme("labplot-axis-horizontal"), i18n("Horizontal Axis"), this);
 	addVerticalAxisAction = new QAction(QIcon::fromTheme("labplot-axis-vertical"), i18n("Vertical Axis"), this);
 	addTextLabelAction = new QAction(QIcon::fromTheme("draw-text"), i18n("Text Label"), this);
 	addCustomPointAction = new QAction(QIcon::fromTheme("draw-cross"), i18n("Custom Point"), this);
 
 	connect(addCurveAction, SIGNAL(triggered()), SLOT(addCurve()));
 	connect(addHistogramAction,SIGNAL(triggered()), SLOT(addHistogram()));
 	connect(addEquationCurveAction, SIGNAL(triggered()), SLOT(addEquationCurve()));
 	connect(addDataReductionCurveAction, SIGNAL(triggered()), SLOT(addDataReductionCurve()));
 	connect(addDifferentiationCurveAction, SIGNAL(triggered()), SLOT(addDifferentiationCurve()));
 	connect(addIntegrationCurveAction, SIGNAL(triggered()), SLOT(addIntegrationCurve()));
 	connect(addInterpolationCurveAction, SIGNAL(triggered()), SLOT(addInterpolationCurve()));
 	connect(addSmoothCurveAction, SIGNAL(triggered()), SLOT(addSmoothCurve()));
 	connect(addFitCurveAction, SIGNAL(triggered()), SLOT(addFitCurve()));
 	connect(addFourierFilterCurveAction, SIGNAL(triggered()), SLOT(addFourierFilterCurve()));
 	connect(addFourierTransformCurveAction, SIGNAL(triggered()), SLOT(addFourierTransformCurve()));
 	connect(addConvolutionCurveAction, SIGNAL(triggered()), SLOT(addConvolutionCurve()));
 	connect(addCorrelationCurveAction, SIGNAL(triggered()), SLOT(addCorrelationCurve()));
 
 	connect(addLegendAction, SIGNAL(triggered()), SLOT(addLegend()));
 	connect(addHorizontalAxisAction, SIGNAL(triggered()), SLOT(addHorizontalAxis()));
 	connect(addVerticalAxisAction, SIGNAL(triggered()), SLOT(addVerticalAxis()));
 	connect(addTextLabelAction, SIGNAL(triggered()), SLOT(addTextLabel()));
 	connect(addCustomPointAction, SIGNAL(triggered()), SLOT(addCustomPoint()));
 
 	//Analysis menu actions
 	addDataOperationAction = new QAction(i18n("Data Operation"), this);
 	addDataReductionAction = new QAction(i18n("Reduce Data"), this);
 	addDifferentiationAction = new QAction(i18n("Differentiate"), this);
 	addIntegrationAction = new QAction(i18n("Integrate"), this);
 	addInterpolationAction = new QAction(i18n("Interpolate"), this);
 	addSmoothAction = new QAction(i18n("Smooth"), this);
 	addConvolutionAction = new QAction(i18n("Convolute/Deconvolute"), this);
 	addCorrelationAction = new QAction(i18n("Correlation"), this);
 
 	QAction* fitAction = new QAction(i18n("Linear"), this);
 	fitAction->setData(PlotDataDialog::FitLinear);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Power"), this);
 	fitAction->setData(PlotDataDialog::FitPower);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Exponential (degree 1)"), this);
 	fitAction->setData(PlotDataDialog::FitExp1);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Exponential (degree 2)"), this);
 	fitAction->setData(PlotDataDialog::FitExp2);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Inverse exponential"), this);
 	fitAction->setData(PlotDataDialog::FitInvExp);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Gauss"), this);
 	fitAction->setData(PlotDataDialog::FitGauss);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Cauchy-Lorentz"), this);
 	fitAction->setData(PlotDataDialog::FitCauchyLorentz);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Arc Tangent"), this);
 	fitAction->setData(PlotDataDialog::FitTan);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Hyperbolic Tangent"), this);
 	fitAction->setData(PlotDataDialog::FitTanh);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Error Function"), this);
 	fitAction->setData(PlotDataDialog::FitErrFunc);
 	addFitAction.append(fitAction);
 
 	fitAction = new QAction(i18n("Custom"), this);
 	fitAction->setData(PlotDataDialog::FitCustom);
 	addFitAction.append(fitAction);
 
 	addFourierFilterAction = new QAction(i18n("Fourier Filter"), this);
 
 	connect(addDataReductionAction, SIGNAL(triggered()), SLOT(addDataReductionCurve()));
 	connect(addDifferentiationAction, SIGNAL(triggered()), SLOT(addDifferentiationCurve()));
 	connect(addIntegrationAction, SIGNAL(triggered()), SLOT(addIntegrationCurve()));
 	connect(addInterpolationAction, SIGNAL(triggered()), SLOT(addInterpolationCurve()));
 	connect(addSmoothAction, SIGNAL(triggered()), SLOT(addSmoothCurve()));
 	connect(addConvolutionAction, SIGNAL(triggered()), SLOT(addConvolutionCurve()));
 	connect(addCorrelationAction, SIGNAL(triggered()), SLOT(addCorrelationCurve()));
 	for (const auto& action : addFitAction)
 		connect(action, SIGNAL(triggered()), SLOT(addFitCurve()));
 	connect(addFourierFilterAction, SIGNAL(triggered()), SLOT(addFourierFilterCurve()));
 
 	//zoom/navigate actions
 	scaleAutoAction = new QAction(QIcon::fromTheme("labplot-auto-scale-all"), i18n("Auto Scale"), this);
 	scaleAutoXAction = new QAction(QIcon::fromTheme("labplot-auto-scale-x"), i18n("Auto Scale X"), this);
 	scaleAutoYAction = new QAction(QIcon::fromTheme("labplot-auto-scale-y"), i18n("Auto Scale Y"), this);
 	zoomInAction = new QAction(QIcon::fromTheme("zoom-in"), i18n("Zoom In"), this);
 	zoomOutAction = new QAction(QIcon::fromTheme("zoom-out"), i18n("Zoom Out"), this);
 	zoomInXAction = new QAction(QIcon::fromTheme("labplot-zoom-in-x"), i18n("Zoom In X"), this);
 	zoomOutXAction = new QAction(QIcon::fromTheme("labplot-zoom-out-x"), i18n("Zoom Out X"), this);
 	zoomInYAction = new QAction(QIcon::fromTheme("labplot-zoom-in-y"), i18n("Zoom In Y"), this);
 	zoomOutYAction = new QAction(QIcon::fromTheme("labplot-zoom-out-y"), i18n("Zoom Out Y"), this);
 	shiftLeftXAction = new QAction(QIcon::fromTheme("labplot-shift-left-x"), i18n("Shift Left X"), this);
 	shiftRightXAction = new QAction(QIcon::fromTheme("labplot-shift-right-x"), i18n("Shift Right X"), this);
 	shiftUpYAction = new QAction(QIcon::fromTheme("labplot-shift-up-y"), i18n("Shift Up Y"), this);
 	shiftDownYAction = new QAction(QIcon::fromTheme("labplot-shift-down-y"), i18n("Shift Down Y"), this);
 
 	connect(scaleAutoAction, SIGNAL(triggered()), SLOT(scaleAuto()));
 	connect(scaleAutoXAction, SIGNAL(triggered()), SLOT(scaleAutoX()));
 	connect(scaleAutoYAction, SIGNAL(triggered()), SLOT(scaleAutoY()));
 	connect(zoomInAction, SIGNAL(triggered()), SLOT(zoomIn()));
 	connect(zoomOutAction, SIGNAL(triggered()), SLOT(zoomOut()));
 	connect(zoomInXAction, SIGNAL(triggered()), SLOT(zoomInX()));
 	connect(zoomOutXAction, SIGNAL(triggered()), SLOT(zoomOutX()));
 	connect(zoomInYAction, SIGNAL(triggered()), SLOT(zoomInY()));
 	connect(zoomOutYAction, SIGNAL(triggered()), SLOT(zoomOutY()));
 	connect(shiftLeftXAction, SIGNAL(triggered()), SLOT(shiftLeftX()));
 	connect(shiftRightXAction, SIGNAL(triggered()), SLOT(shiftRightX()));
 	connect(shiftUpYAction, SIGNAL(triggered()), SLOT(shiftUpY()));
 	connect(shiftDownYAction, SIGNAL(triggered()), SLOT(shiftDownY()));
 
 	//visibility action
 	visibilityAction = new QAction(i18n("Visible"), this);
 	visibilityAction->setCheckable(true);
 	connect(visibilityAction, SIGNAL(triggered()), this, SLOT(visibilityChanged()));
 }
 
 void CartesianPlot::initMenus() {
 	initActions();
 
 	addNewMenu = new QMenu(i18n("Add New"));
 	addNewMenu->addAction(addCurveAction);
 	addNewMenu->addAction(addHistogramAction);
 	addNewMenu->addAction(addEquationCurveAction);
 	addNewMenu->addSeparator();
 	addNewMenu->addAction(addDataReductionCurveAction);
 	addNewMenu->addAction(addDifferentiationCurveAction);
 	addNewMenu->addAction(addIntegrationCurveAction);
 	addNewMenu->addAction(addInterpolationCurveAction);
 	addNewMenu->addAction(addSmoothCurveAction);
 	addNewMenu->addAction(addFitCurveAction);
 	addNewMenu->addAction(addFourierFilterCurveAction);
 	addNewMenu->addAction(addFourierTransformCurveAction);
 	addNewMenu->addAction(addConvolutionCurveAction);
 	addNewMenu->addAction(addCorrelationCurveAction);
 	addNewMenu->addSeparator();
 	addNewMenu->addAction(addLegendAction);
 	addNewMenu->addSeparator();
 	addNewMenu->addAction(addHorizontalAxisAction);
 	addNewMenu->addAction(addVerticalAxisAction);
 	addNewMenu->addSeparator();
 	addNewMenu->addAction(addTextLabelAction);
 	addNewMenu->addSeparator();
 	addNewMenu->addAction(addCustomPointAction);
 
 	zoomMenu = new QMenu(i18n("Zoom"));
 	zoomMenu->addAction(scaleAutoAction);
 	zoomMenu->addAction(scaleAutoXAction);
 	zoomMenu->addAction(scaleAutoYAction);
 	zoomMenu->addSeparator();
 	zoomMenu->addAction(zoomInAction);
 	zoomMenu->addAction(zoomOutAction);
 	zoomMenu->addSeparator();
 	zoomMenu->addAction(zoomInXAction);
 	zoomMenu->addAction(zoomOutXAction);
 	zoomMenu->addSeparator();
 	zoomMenu->addAction(zoomInYAction);
 	zoomMenu->addAction(zoomOutYAction);
 	zoomMenu->addSeparator();
 	zoomMenu->addAction(shiftLeftXAction);
 	zoomMenu->addAction(shiftRightXAction);
 	zoomMenu->addSeparator();
 	zoomMenu->addAction(shiftUpYAction);
 	zoomMenu->addAction(shiftDownYAction);
 
 	// Data manipulation menu
 	QMenu* dataManipulationMenu = new QMenu(i18n("Data Manipulation"));
 	dataManipulationMenu->setIcon(QIcon::fromTheme("zoom-draw"));
 	dataManipulationMenu->addAction(addDataOperationAction);
 	dataManipulationMenu->addAction(addDataReductionAction);
 
 	// Data fit menu
 	QMenu* dataFitMenu = new QMenu(i18n("Fit"));
 	dataFitMenu->setIcon(QIcon::fromTheme("labplot-xy-fit-curve"));
 	dataFitMenu->addAction(addFitAction.at(0));
 	dataFitMenu->addAction(addFitAction.at(1));
 	dataFitMenu->addAction(addFitAction.at(2));
 	dataFitMenu->addAction(addFitAction.at(3));
 	dataFitMenu->addAction(addFitAction.at(4));
 	dataFitMenu->addSeparator();
 	dataFitMenu->addAction(addFitAction.at(5));
 	dataFitMenu->addAction(addFitAction.at(6));
 	dataFitMenu->addSeparator();
 	dataFitMenu->addAction(addFitAction.at(7));
 	dataFitMenu->addAction(addFitAction.at(8));
 	dataFitMenu->addAction(addFitAction.at(9));
 	dataFitMenu->addSeparator();
 	dataFitMenu->addAction(addFitAction.at(10));
 
 	//analysis menu
 	dataAnalysisMenu = new QMenu(i18n("Analysis"));
 	dataAnalysisMenu->insertMenu(nullptr, dataManipulationMenu);
 	dataAnalysisMenu->addSeparator();
 	dataAnalysisMenu->addAction(addDifferentiationAction);
 	dataAnalysisMenu->addAction(addIntegrationAction);
 	dataAnalysisMenu->addSeparator();
 	dataAnalysisMenu->addAction(addInterpolationAction);
 	dataAnalysisMenu->addAction(addSmoothAction);
 	dataAnalysisMenu->addAction(addFourierFilterAction);
 	dataAnalysisMenu->addAction(addConvolutionAction);
 	dataAnalysisMenu->addAction(addCorrelationAction);
 	dataAnalysisMenu->addSeparator();
 	dataAnalysisMenu->addMenu(dataFitMenu);
 
 	//themes menu
 	themeMenu = new QMenu(i18n("Apply Theme"));
 	auto* themeWidget = new ThemesWidget(nullptr);
 	connect(themeWidget, SIGNAL(themeSelected(QString)), this, SLOT(loadTheme(QString)));
 	connect(themeWidget, SIGNAL(themeSelected(QString)), themeMenu, SLOT(close()));
 
 	auto* widgetAction = new QWidgetAction(this);
 	widgetAction->setDefaultWidget(themeWidget);
 	themeMenu->addAction(widgetAction);
 
 	m_menusInitialized = true;
 }
 
 QMenu* CartesianPlot::createContextMenu() {
 	if (!m_menusInitialized)
 		initMenus();
 
 	QMenu* menu = WorksheetElement::createContextMenu();
 	QAction* firstAction = menu->actions().at(1);
 
 	visibilityAction->setChecked(isVisible());
 	menu->insertAction(firstAction, visibilityAction);
 
 	menu->insertMenu(firstAction, addNewMenu);
 	menu->insertMenu(firstAction, zoomMenu);
 	menu->insertSeparator(firstAction);
 	menu->insertMenu(firstAction, themeMenu);
 	menu->insertSeparator(firstAction);
 
 	return menu;
 }
 
 QMenu* CartesianPlot::analysisMenu() {
 	if (!m_menusInitialized)
 		initMenus();
 
 	return dataAnalysisMenu;
 }
 
 /*!
 	Returns an icon to be used in the project explorer.
 */
 QIcon CartesianPlot::icon() const {
 	return QIcon::fromTheme("office-chart-line");
 }
 
 QVector<AbstractAspect*> CartesianPlot::dependsOn() const {
 	//aspects which the plotted data in the worksheet depends on (spreadsheets and later matrices)
 	QVector<AbstractAspect*> aspects;
 
 	for (const auto* curve : children<XYCurve>()) {
 		if (curve->xColumn() && dynamic_cast<Spreadsheet*>(curve->xColumn()->parentAspect()) )
 			aspects << curve->xColumn()->parentAspect();
 
 		if (curve->yColumn() && dynamic_cast<Spreadsheet*>(curve->yColumn()->parentAspect()) )
 			aspects << curve->yColumn()->parentAspect();
 	}
 
 	return aspects;
 }
 
 void CartesianPlot::navigate(CartesianPlot::NavigationOperation op) {
 	if (op == ScaleAuto) scaleAuto();
 	else if (op == ScaleAutoX) scaleAutoX();
 	else if (op == ScaleAutoY) scaleAutoY();
 	else if (op == ZoomIn) zoomIn();
 	else if (op == ZoomOut) zoomOut();
 	else if (op == ZoomInX) zoomInX();
 	else if (op == ZoomOutX) zoomOutX();
 	else if (op == ZoomInY) zoomInY();
 	else if (op == ZoomOutY) zoomOutY();
 	else if (op == ShiftLeftX) shiftLeftX();
 	else if (op == ShiftRightX) shiftRightX();
 	else if (op == ShiftUpY) shiftUpY();
 	else if (op == ShiftDownY) shiftDownY();
 }
 
 void CartesianPlot::setSuppressDataChangedSignal(bool value) {
 	Q_D(CartesianPlot);
 	d->suppressRetransform = value;
 }
 
 void CartesianPlot::processDropEvent(QDropEvent* event) {
 	PERFTRACE("CartesianPlot::processDropEvent");
 	const QMimeData* mimeData = event->mimeData();
 	if (!mimeData)
 		return;
 
 	//deserialize the mime data to the vector of aspect pointers
 	QByteArray data = mimeData->data(QLatin1String("labplot-dnd"));
 	QVector<quintptr> vec;
 	QDataStream stream(&data, QIODevice::ReadOnly);
 	stream >> vec;
 	QVector<AbstractColumn*> columns;
 	for (auto a : vec) {
 		auto* aspect = (AbstractAspect*)a;
 		auto* column = dynamic_cast<AbstractColumn*>(aspect);
 		if (column)
 			columns << column;
 	}
 
 	//return if there are no columns being dropped.
 	//TODO: extend this later when we allow to drag&drop plots, etc.
 	if (columns.isEmpty())
 		return;
 
 	//determine the first column with "x plot designation" as the x-data column for all curves to be created
 	const AbstractColumn* xColumn = nullptr;
 	for (const auto* column : columns) {
 		if (column->plotDesignation() == AbstractColumn::X) {
 			xColumn = column;
 			break;
 		}
 	}
 
 	//if no column with "x plot designation" is available, use the x-data column of the first curve in the plot,
 	if (xColumn == nullptr) {
 		QVector<XYCurve*> curves = children<XYCurve>();
 		if (!curves.isEmpty())
 			xColumn = curves.at(0)->xColumn();
 	}
 
 	//use the first dropped column if no column with "x plot designation" nor curves are available
 	if (xColumn == nullptr)
 		xColumn = columns.at(0);
 
 	//create curves
 	bool curvesAdded = false;
 	for (const auto* column : columns) {
 		if (column == xColumn)
 			continue;
 
 		XYCurve* curve = new XYCurve(column->name());
 		curve->suppressRetransform(true); //suppress retransform, all curved will be recalculated at the end
 		curve->setXColumn(xColumn);
 		curve->setYColumn(column);
 		addChild(curve);
 		curve->suppressRetransform(false);
 		curvesAdded = true;
 	}
 
 	if (curvesAdded)
 		dataChanged();
 }
 
 
 bool CartesianPlot::isPanningActive() const {
 	Q_D(const CartesianPlot);
 	return d->panningStarted;
 }
 
 //##############################################################################
 //################################  getter methods  ############################
 //##############################################################################
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, CartesianPlot::RangeType, rangeType, rangeType)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, CartesianPlot::RangeFormat, xRangeFormat, xRangeFormat)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, CartesianPlot::RangeFormat, yRangeFormat, yRangeFormat)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, int, rangeLastValues, rangeLastValues)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, int, rangeFirstValues, rangeFirstValues)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, bool, autoScaleX, autoScaleX)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, double, xMin, xMin)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, double, xMax, xMax)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, CartesianPlot::Scale, xScale, xScale)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, bool, xRangeBreakingEnabled, xRangeBreakingEnabled)
 CLASS_SHARED_D_READER_IMPL(CartesianPlot, CartesianPlot::RangeBreaks, xRangeBreaks, xRangeBreaks)
 
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, bool, autoScaleY, autoScaleY)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, double, yMin, yMin)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, double, yMax, yMax)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, CartesianPlot::Scale, yScale, yScale)
 BASIC_SHARED_D_READER_IMPL(CartesianPlot, bool, yRangeBreakingEnabled, yRangeBreakingEnabled)
 CLASS_SHARED_D_READER_IMPL(CartesianPlot, CartesianPlot::RangeBreaks, yRangeBreaks, yRangeBreaks)
 
 CLASS_SHARED_D_READER_IMPL(CartesianPlot, QString, theme, theme)
 
 /*!
 	returns the actual bounding rectangular of the plot area showing data (plot's rectangular minus padding)
 	in plot's coordinates
  */
 QRectF CartesianPlot::dataRect() const {
 	Q_D(const CartesianPlot);
 	return d->dataRect;
 }
 
 CartesianPlot::MouseMode CartesianPlot::mouseMode() const {
 	Q_D(const CartesianPlot);
 	return d->mouseMode;
 }
 
 const QString& CartesianPlot::xRangeDateTimeFormat() const {
 	Q_D(const CartesianPlot);
 	return d->xRangeDateTimeFormat;
 }
 
 const QString& CartesianPlot::yRangeDateTimeFormat() const {
 	Q_D(const CartesianPlot);
 	return d->yRangeDateTimeFormat;
 }
 
 //##############################################################################
 //######################  setter methods and undo commands  ####################
 //##############################################################################
 /*!
 	set the rectangular, defined in scene coordinates
  */
 class CartesianPlotSetRectCmd : public QUndoCommand {
 public:
 	CartesianPlotSetRectCmd(CartesianPlotPrivate* private_obj, QRectF rect) : m_private(private_obj), m_rect(rect) {
 		setText(i18n("%1: change geometry rect", m_private->name()));
 	};
 
 	void redo() override {
 		QRectF tmp = m_private->rect;
 		//TODO:
 // 		const double horizontalRatio = m_rect.width() / m_private->rect.width();
 // 		const double verticalRatio = m_rect.height() / m_private->rect.height();
 // 		m_private->q->handleResize(horizontalRatio, verticalRatio, false);
 		m_private->rect = m_rect;
 		m_rect = tmp;
 		m_private->retransform();
 		emit m_private->q->rectChanged(m_private->rect);
 	};
 
 	void undo() override {
 		redo();
 	}
 
 private:
 	CartesianPlotPrivate* m_private;
 	QRectF m_rect;
 };
 
 void CartesianPlot::setRect(const QRectF& rect) {
 	Q_D(CartesianPlot);
 	if (rect != d->rect)
 		exec(new CartesianPlotSetRectCmd(d, rect));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetRangeType, CartesianPlot::RangeType, rangeType, rangeChanged);
 void CartesianPlot::setRangeType(RangeType type) {
 	Q_D(CartesianPlot);
 	if (type != d->rangeType)
 		exec(new CartesianPlotSetRangeTypeCmd(d, type, ki18n("%1: set range type")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetXRangeFormat, CartesianPlot::RangeFormat, xRangeFormat, xRangeFormatChanged);
 void CartesianPlot::setXRangeFormat(RangeFormat format) {
 	Q_D(CartesianPlot);
 	if (format != d->xRangeFormat)
 		exec(new CartesianPlotSetXRangeFormatCmd(d, format, ki18n("%1: set x-range format")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetYRangeFormat, CartesianPlot::RangeFormat, yRangeFormat, yRangeFormatChanged);
 void CartesianPlot::setYRangeFormat(RangeFormat format) {
 	Q_D(CartesianPlot);
 	if (format != d->yRangeFormat)
 		exec(new CartesianPlotSetYRangeFormatCmd(d, format, ki18n("%1: set y-range format")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetRangeLastValues, int, rangeLastValues, rangeChanged);
 void CartesianPlot::setRangeLastValues(int values) {
 	Q_D(CartesianPlot);
 	if (values != d->rangeLastValues)
 		exec(new CartesianPlotSetRangeLastValuesCmd(d, values, ki18n("%1: set range")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetRangeFirstValues, int, rangeFirstValues, rangeChanged);
 void CartesianPlot::setRangeFirstValues(int values) {
 	Q_D(CartesianPlot);
 	if (values != d->rangeFirstValues)
 		exec(new CartesianPlotSetRangeFirstValuesCmd(d, values, ki18n("%1: set range")));
 }
 
 
 class CartesianPlotSetAutoScaleXCmd : public QUndoCommand {
 public:
 	CartesianPlotSetAutoScaleXCmd(CartesianPlotPrivate* private_obj, bool autoScale) :
 		m_private(private_obj), m_autoScale(autoScale), m_autoScaleOld(false), m_minOld(0.0), m_maxOld(0.0) {
 		setText(i18n("%1: change x-range auto scaling", m_private->name()));
 	};
 
 	void redo() override {
 		m_autoScaleOld = m_private->autoScaleX;
 		if (m_autoScale) {
 			m_minOld = m_private->xMin;
 			m_maxOld = m_private->xMax;
 			m_private->q->scaleAutoX();
 		}
 		m_private->autoScaleX = m_autoScale;
 		emit m_private->q->xAutoScaleChanged(m_autoScale);
 	};
 
 	void undo() override {
 		if (!m_autoScaleOld) {
 			m_private->xMin = m_minOld;
 			m_private->xMax = m_maxOld;
 			m_private->retransformScales();
 		}
 		m_private->autoScaleX = m_autoScaleOld;
 		emit m_private->q->xAutoScaleChanged(m_autoScaleOld);
 	}
 
 private:
 	CartesianPlotPrivate* m_private;
 	bool m_autoScale;
 	bool m_autoScaleOld;
 	double m_minOld;
 	double m_maxOld;
 };
 
 void CartesianPlot::setAutoScaleX(bool autoScaleX) {
 	Q_D(CartesianPlot);
 	if (autoScaleX != d->autoScaleX)
 		exec(new CartesianPlotSetAutoScaleXCmd(d, autoScaleX));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetXMin, double, xMin, retransformScales)
 void CartesianPlot::setXMin(double xMin) {
 	Q_D(CartesianPlot);
 	if (xMin != d->xMin)
 		exec(new CartesianPlotSetXMinCmd(d, xMin, ki18n("%1: set min x")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetXMax, double, xMax, retransformScales)
 void CartesianPlot::setXMax(double xMax) {
 	Q_D(CartesianPlot);
 	if (xMax != d->xMax)
 		exec(new CartesianPlotSetXMaxCmd(d, xMax, ki18n("%1: set max x")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetXScale, CartesianPlot::Scale, xScale, retransformScales)
 void CartesianPlot::setXScale(Scale scale) {
 	Q_D(CartesianPlot);
 	if (scale != d->xScale)
 		exec(new CartesianPlotSetXScaleCmd(d, scale, ki18n("%1: set x scale")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetXRangeBreakingEnabled, bool, xRangeBreakingEnabled, retransformScales)
 void CartesianPlot::setXRangeBreakingEnabled(bool enabled) {
 	Q_D(CartesianPlot);
 	if (enabled != d->xRangeBreakingEnabled)
 		exec(new CartesianPlotSetXRangeBreakingEnabledCmd(d, enabled, ki18n("%1: x-range breaking enabled")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetXRangeBreaks, CartesianPlot::RangeBreaks, xRangeBreaks, retransformScales)
 void CartesianPlot::setXRangeBreaks(const RangeBreaks& breakings) {
 	Q_D(CartesianPlot);
 	exec(new CartesianPlotSetXRangeBreaksCmd(d, breakings, ki18n("%1: x-range breaks changed")));
 }
 
 class CartesianPlotSetAutoScaleYCmd : public QUndoCommand {
 public:
 	CartesianPlotSetAutoScaleYCmd(CartesianPlotPrivate* private_obj, bool autoScale) :
 		m_private(private_obj), m_autoScale(autoScale), m_autoScaleOld(false), m_minOld(0.0), m_maxOld(0.0) {
 		setText(i18n("%1: change y-range auto scaling", m_private->name()));
 	};
 
 	void redo() override {
 		m_autoScaleOld = m_private->autoScaleY;
 		if (m_autoScale) {
 			m_minOld = m_private->yMin;
 			m_maxOld = m_private->yMax;
 			m_private->q->scaleAutoY();
 		}
 		m_private->autoScaleY = m_autoScale;
 		emit m_private->q->yAutoScaleChanged(m_autoScale);
 	};
 
 	void undo() override {
 		if (!m_autoScaleOld) {
 			m_private->yMin = m_minOld;
 			m_private->yMax = m_maxOld;
 			m_private->retransformScales();
 		}
 		m_private->autoScaleY = m_autoScaleOld;
 		emit m_private->q->yAutoScaleChanged(m_autoScaleOld);
 	}
 
 private:
 	CartesianPlotPrivate* m_private;
 	bool m_autoScale;
 	bool m_autoScaleOld;
 	double m_minOld;
 	double m_maxOld;
 };
 
 void CartesianPlot::setAutoScaleY(bool autoScaleY) {
 	Q_D(CartesianPlot);
 	if (autoScaleY != d->autoScaleY)
 		exec(new CartesianPlotSetAutoScaleYCmd(d, autoScaleY));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetYMin, double, yMin, retransformScales)
 void CartesianPlot::setYMin(double yMin) {
 	Q_D(CartesianPlot);
 	if (yMin != d->yMin)
 		exec(new CartesianPlotSetYMinCmd(d, yMin, ki18n("%1: set min y")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetYMax, double, yMax, retransformScales)
 void CartesianPlot::setYMax(double yMax) {
 	Q_D(CartesianPlot);
 	if (yMax != d->yMax)
 		exec(new CartesianPlotSetYMaxCmd(d, yMax, ki18n("%1: set max y")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetYScale, CartesianPlot::Scale, yScale, retransformScales)
 void CartesianPlot::setYScale(Scale scale) {
 	Q_D(CartesianPlot);
 	if (scale != d->yScale)
 		exec(new CartesianPlotSetYScaleCmd(d, scale, ki18n("%1: set y scale")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetYRangeBreakingEnabled, bool, yRangeBreakingEnabled, retransformScales)
 void CartesianPlot::setYRangeBreakingEnabled(bool enabled) {
 	Q_D(CartesianPlot);
 	if (enabled != d->yRangeBreakingEnabled)
 		exec(new CartesianPlotSetYRangeBreakingEnabledCmd(d, enabled, ki18n("%1: y-range breaking enabled")));
 }
 
 STD_SETTER_CMD_IMPL_F_S(CartesianPlot, SetYRangeBreaks, CartesianPlot::RangeBreaks, yRangeBreaks, retransformScales)
 void CartesianPlot::setYRangeBreaks(const RangeBreaks& breaks) {
 	Q_D(CartesianPlot);
 	exec(new CartesianPlotSetYRangeBreaksCmd(d, breaks, ki18n("%1: y-range breaks changed")));
 }
 
 STD_SETTER_CMD_IMPL_S(CartesianPlot, SetTheme, QString, theme)
 void CartesianPlot::setTheme(const QString& theme) {
 	Q_D(CartesianPlot);
 	if (theme != d->theme) {
 		if (!theme.isEmpty()) {
 			beginMacro( i18n("%1: load theme %2", name(), theme) );
 			exec(new CartesianPlotSetThemeCmd(d, theme, ki18n("%1: set theme")));
 			loadTheme(theme);
 			endMacro();
 		} else
 			exec(new CartesianPlotSetThemeCmd(d, theme, ki18n("%1: disable theming")));
 	}
 }
 
 //################################################################
 //########################## Slots ###############################
 //################################################################
 void CartesianPlot::addHorizontalAxis() {
 	Axis* axis = new Axis("x-axis", Axis::AxisHorizontal);
 	if (axis->autoScale()) {
 		axis->setUndoAware(false);
 		axis->setStart(xMin());
 		axis->setEnd(xMax());
 		axis->setUndoAware(true);
 	}
 	addChild(axis);
 }
 
 void CartesianPlot::addVerticalAxis() {
 	Axis* axis = new Axis("y-axis", Axis::AxisVertical);
 	if (axis->autoScale()) {
 		axis->setUndoAware(false);
 		axis->setStart(yMin());
 		axis->setEnd(yMax());
 		axis->setUndoAware(true);
 	}
 	addChild(axis);
 }
 
 void CartesianPlot::addCurve() {
 	addChild(new XYCurve("xy-curve"));
 }
 
 void CartesianPlot::addEquationCurve() {
 	addChild(new XYEquationCurve("f(x)"));
 }
 
 void CartesianPlot::addHistogram() {
 	addChild(new Histogram("Histogram"));
 }
 
 /*!
  * returns the first selected XYCurve in the plot
  */
 const XYCurve* CartesianPlot::currentCurve() const {
 	for (const auto* curve : this->children<const XYCurve>()) {
 		if (curve->graphicsItem()->isSelected())
 			return curve;
 	}
 
 	return nullptr;
 }
 
 void CartesianPlot::addDataReductionCurve() {
 	XYDataReductionCurve* curve = new XYDataReductionCurve("Data reduction");
 	const XYCurve* curCurve = currentCurve();
 	if (curCurve) {
 		beginMacro( i18n("%1: reduce '%2'", name(), curCurve->name()) );
 		curve->setName( i18n("Reduction of '%1'", curCurve->name()) );
 		curve->setDataSourceType(XYAnalysisCurve::DataSourceCurve);
 		curve->setDataSourceCurve(curCurve);
 		this->addChild(curve);
 		curve->recalculate();
 		emit curve->dataReductionDataChanged(curve->dataReductionData());
 	} else {
 		beginMacro(i18n("%1: add data reduction curve", name()));
 		this->addChild(curve);
 	}
 
 	endMacro();
 }
 
 void CartesianPlot::addDifferentiationCurve() {
 	XYDifferentiationCurve* curve = new XYDifferentiationCurve("Differentiation");
 	const XYCurve* curCurve = currentCurve();
 	if (curCurve) {
 		beginMacro( i18n("%1: differentiate '%2'", name(), curCurve->name()) );
 		curve->setName( i18n("Derivative of '%1'", curCurve->name()) );
 		curve->setDataSourceType(XYAnalysisCurve::DataSourceCurve);
 		curve->setDataSourceCurve(curCurve);
 		this->addChild(curve);
 		curve->recalculate();
 		emit curve->differentiationDataChanged(curve->differentiationData());
 	} else {
 		beginMacro(i18n("%1: add differentiation curve", name()));
 		this->addChild(curve);
 	}
 
 	endMacro();
 }
 
 void CartesianPlot::addIntegrationCurve() {
 	XYIntegrationCurve* curve = new XYIntegrationCurve("Integration");
 	const XYCurve* curCurve = currentCurve();
 	if (curCurve) {
 		beginMacro( i18n("%1: integrate '%2'", name(), curCurve->name()) );
 		curve->setName( i18n("Integral of '%1'", curCurve->name()) );
 		curve->setDataSourceType(XYAnalysisCurve::DataSourceCurve);
 		curve->setDataSourceCurve(curCurve);
 		this->addChild(curve);
 		curve->recalculate();
 		emit curve->integrationDataChanged(curve->integrationData());
 	} else {
 		beginMacro(i18n("%1: add integration curve", name()));
 		this->addChild(curve);
 	}
 
 	endMacro();
 }
 
 void CartesianPlot::addInterpolationCurve() {
 	XYInterpolationCurve* curve = new XYInterpolationCurve("Interpolation");
 	const XYCurve* curCurve = currentCurve();
 	if (curCurve) {
 		beginMacro( i18n("%1: interpolate '%2'", name(), curCurve->name()) );
 		curve->setName( i18n("Interpolation of '%1'", curCurve->name()) );
 		curve->setDataSourceType(XYAnalysisCurve::DataSourceCurve);
 		curve->setDataSourceCurve(curCurve);
 		curve->recalculate();
 		this->addChild(curve);
 		emit curve->interpolationDataChanged(curve->interpolationData());
 	} else {
 		beginMacro(i18n("%1: add interpolation curve", name()));
 		this->addChild(curve);
 	}
 
 	endMacro();
 }
 
 void CartesianPlot::addSmoothCurve() {
 	XYSmoothCurve* curve = new XYSmoothCurve("Smooth");
 	const XYCurve* curCurve = currentCurve();
 	if (curCurve) {
 		beginMacro( i18n("%1: smooth '%2'", name(), curCurve->name()) );
 		curve->setName( i18n("Smoothing of '%1'", curCurve->name()) );
 		curve->setDataSourceType(XYAnalysisCurve::DataSourceCurve);
 		curve->setDataSourceCurve(curCurve);
 		this->addChild(curve);
 		curve->recalculate();
 		emit curve->smoothDataChanged(curve->smoothData());
 	} else {
 		beginMacro(i18n("%1: add smoothing curve", name()));
 		this->addChild(curve);
 	}
 
 	endMacro();
 }
 
 void CartesianPlot::addFitCurve() {
 	DEBUG("CartesianPlot::addFitCurve()");
 	XYFitCurve* curve = new XYFitCurve("fit");
 	const XYCurve* curCurve = currentCurve();
 	if (curCurve) {
 		beginMacro( i18n("%1: fit to '%2'", name(), curCurve->name()) );
 		curve->setName( i18n("Fit to '%1'", curCurve->name()) );
 		curve->setDataSourceType(XYAnalysisCurve::DataSourceCurve);
 		curve->setDataSourceCurve(curCurve);
 
 
 		//set the fit model category and type
 		const auto* action = qobject_cast<const QAction*>(QObject::sender());
 		PlotDataDialog::AnalysisAction type = (PlotDataDialog::AnalysisAction)action->data().toInt();
 		curve->initFitData(type);
 		curve->initStartValues(curCurve);
 
 		//fit with weights for y if the curve has error bars for y
 		if (curCurve->yErrorType() == XYCurve::SymmetricError && curCurve->yErrorPlusColumn()) {
 			XYFitCurve::FitData fitData = curve->fitData();
 			fitData.yWeightsType = nsl_fit_weight_instrumental;
 			curve->setFitData(fitData);
 			curve->setYErrorColumn(curCurve->yErrorPlusColumn());
 		}
 
 		this->addChild(curve);
 		curve->recalculate();
 		emit curve->fitDataChanged(curve->fitData());
 	} else {
 		beginMacro(i18n("%1: add fit curve", name()));
 		this->addChild(curve);
 	}
 
 	endMacro();
 }
 
 void CartesianPlot::addFourierFilterCurve() {
 	XYFourierFilterCurve* curve = new XYFourierFilterCurve("Fourier filter");
 	const XYCurve* curCurve = currentCurve();
 	if (curCurve) {
 		beginMacro( i18n("%1: Fourier filtering of '%2'", name(), curCurve->name()) );
 		curve->setName( i18n("Fourier filtering of '%1'", curCurve->name()) );
 		curve->setDataSourceType(XYAnalysisCurve::DataSourceCurve);
 		curve->setDataSourceCurve(curCurve);
 		this->addChild(curve);
 	} else {
 		beginMacro(i18n("%1: add Fourier filter curve", name()));
 		this->addChild(curve);
 	}
 
 	endMacro();
 }
 
 void CartesianPlot::addFourierTransformCurve() {
 	XYFourierTransformCurve* curve = new XYFourierTransformCurve("Fourier transform");
 	this->addChild(curve);
 }
 
 void CartesianPlot::addConvolutionCurve() {
 	XYConvolutionCurve* curve = new XYConvolutionCurve("Convolution");
 	this->addChild(curve);
 }
 
 void CartesianPlot::addCorrelationCurve() {
 	XYCorrelationCurve* curve = new XYCorrelationCurve("Correlation");
 	this->addChild(curve);
 }
 
 /*!
  * public helper function to set a legend object created outside of CartesianPlot, e.g. in \c OriginProjectParser.
  */
 void CartesianPlot::addLegend(CartesianPlotLegend* legend) {
 	m_legend = legend;
 	this->addChild(legend);
 }
 
 void CartesianPlot::addLegend() {
 	//don't do anything if there's already a legend
 	if (m_legend)
 		return;
 
 	m_legend = new CartesianPlotLegend(this, "legend");
 	this->addChild(m_legend);
 	m_legend->retransform();
 
 	//only one legend is allowed -> disable the action
 	if (m_menusInitialized)
 		addLegendAction->setEnabled(false);
 }
 
 void CartesianPlot::addTextLabel() {
 	TextLabel* label = new TextLabel("text label");
 	this->addChild(label);
 	label->setParentGraphicsItem(graphicsItem());
 }
 
 void CartesianPlot::addCustomPoint() {
 	CustomPoint* point = new CustomPoint(this, "custom point");
 	this->addChild(point);
 }
 
 void CartesianPlot::childAdded(const AbstractAspect* child) {
 	Q_D(CartesianPlot);
 	const auto* curve = qobject_cast<const XYCurve*>(child);
 	if (curve) {
 		connect(curve, SIGNAL(dataChanged()), this, SLOT(dataChanged()));
 		connect(curve, SIGNAL(xDataChanged()), this, SLOT(xDataChanged()));
 		connect(curve, SIGNAL(yDataChanged()), this, SLOT(yDataChanged()));
 		connect(curve, SIGNAL(visibilityChanged(bool)), this, SLOT(curveVisibilityChanged()));
 
 		//update the legend on changes of the name, line and symbol styles
 		connect(curve, SIGNAL(aspectDescriptionChanged(const AbstractAspect*)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(lineTypeChanged(XYCurve::LineType)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(linePenChanged(QPen)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(lineOpacityChanged(qreal)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(symbolsStyleChanged(Symbol::Style)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(symbolsSizeChanged(qreal)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(symbolsRotationAngleChanged(qreal)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(symbolsOpacityChanged(qreal)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(symbolsBrushChanged(QBrush)), this, SLOT(updateLegend()));
 		connect(curve, SIGNAL(symbolsPenChanged(QPen)), this, SLOT(updateLegend()));
 
 		updateLegend();
 		d->curvesXMinMaxIsDirty = true;
 		d->curvesYMinMaxIsDirty = true;
 
 		//in case the first curve is added, check whether we start plotting datetime data
 		if (children<XYCurve>().size() == 1) {
 			const auto* col = dynamic_cast<const Column*>(curve->xColumn());
 			if (col) {
 				if (col->columnMode() == AbstractColumn::DateTime) {
 					setUndoAware(false);
 					setXRangeFormat(CartesianPlot::DateTime);
 					setUndoAware(true);
 
 					//set column's datetime format for all horizontal axis
 					for (auto* axis : children<Axis>()) {
 						if (axis->orientation() == Axis::AxisHorizontal) {
 							auto* filter = static_cast<DateTime2StringFilter*>(col->outputFilter());
 							d->xRangeDateTimeFormat = filter->format();
 							axis->setUndoAware(false);
 							axis->setLabelsDateTimeFormat(d->xRangeDateTimeFormat);
 							axis->setUndoAware(true);
 						}
 					}
 				}
 			}
 
 			col = dynamic_cast<const Column*>(curve->yColumn());
 			if (col) {
 				if (col->columnMode() == AbstractColumn::DateTime) {
 					setUndoAware(false);
 					setYRangeFormat(CartesianPlot::DateTime);
 					setUndoAware(true);
 
 					//set column's datetime format for all vertical axis
 					for (auto* axis : children<Axis>()) {
 						if (axis->orientation() == Axis::AxisVertical) {
 							auto* filter = static_cast<DateTime2StringFilter*>(col->outputFilter());
 							d->yRangeDateTimeFormat = filter->format();
 							axis->setUndoAware(false);
 							axis->setLabelsDateTimeFormat(d->yRangeDateTimeFormat);
 							axis->setUndoAware(true);
 						}
 					}
 				}
 			}
 		}
 	} else {
 		const auto* hist = qobject_cast<const Histogram*>(child);
 		if (hist) {
 			connect(hist, &Histogram::dataChanged, this, &CartesianPlot::dataChanged);
 			connect(hist, &Histogram::visibilityChanged, this, &CartesianPlot::curveVisibilityChanged);
 
 			updateLegend();
 		}
 	}
 
 	if (!isLoading()) {
 		//if a theme was selected, apply the theme settings for newly added children, too
 		if (!d->theme.isEmpty()) {
 			const auto* elem = dynamic_cast<const WorksheetElement*>(child);
 			if (elem) {
 				KConfig config(ThemeHandler::themeFilePath(d->theme), KConfig::SimpleConfig);
 				const_cast<WorksheetElement*>(elem)->loadThemeConfig(config);
 			}
 		} else {
 			//no theme is available, apply the default colors for curves only, s.a. XYCurve::loadThemeConfig()
 			const auto* curve = dynamic_cast<const XYCurve*>(child);
 			if (curve) {
 				int index = indexOfChild<XYCurve>(curve);
 				QColor themeColor;
 				if (index < m_themeColorPalette.size())
 					themeColor = m_themeColorPalette.at(index);
 				else {
 					if (m_themeColorPalette.size())
 						themeColor = m_themeColorPalette.last();
 				}
 
 				auto* c = const_cast<XYCurve*>(curve);
 
 				//Line
 				QPen p = curve->linePen();
 				p.setColor(themeColor);
 				c->setLinePen(p);
 
 				//Drop line
 				p = curve->dropLinePen();
 				p.setColor(themeColor);
 				c->setDropLinePen(p);
 
 				//Symbol
 				QBrush brush = c->symbolsBrush();
 				brush.setColor(themeColor);
 				c->setSymbolsBrush(brush);
 				p = c->symbolsPen();
 				p.setColor(themeColor);
 				c->setSymbolsPen(p);
 
 				//Filling
 				c->setFillingFirstColor(themeColor);
 
 				//Error bars
 				p.setColor(themeColor);
 				c->setErrorBarsPen(p);
 			}
 		}
 	}
 }
 
 void CartesianPlot::childRemoved(const AbstractAspect* parent, const AbstractAspect* before, const AbstractAspect* child) {
 	Q_UNUSED(parent);
 	Q_UNUSED(before);
 	if (m_legend == child) {
 		if (m_menusInitialized)
 			addLegendAction->setEnabled(true);
 		m_legend = nullptr;
 	} else {
 		const auto* curve = qobject_cast<const XYCurve*>(child);
 		if (curve)
 			updateLegend();
 	}
 }
 
 void CartesianPlot::updateLegend() {
 	if (m_legend)
 		m_legend->retransform();
 }
 
 /*!
 	called when in one of the curves the data was changed.
 	Autoscales the coordinate system and the x-axes, when "auto-scale" is active.
 */
 void CartesianPlot::dataChanged() {
 	Q_D(CartesianPlot);
 	d->curvesXMinMaxIsDirty = true;
 	d->curvesYMinMaxIsDirty = true;
 	if (d->autoScaleX && d->autoScaleY)
 		this->scaleAuto();
 	else if (d->autoScaleX)
 		this->scaleAutoX();
 	else if (d->autoScaleY)
 		this->scaleAutoY();
 	else {
 		//free ranges -> rentransform the curve that sent
 		auto* curve = dynamic_cast<XYCurve*>(QObject::sender());
 		if (curve)
 			curve->retransform();
 		else {
 			auto* hist = dynamic_cast<Histogram*>(QObject::sender());
 			if (hist)
 				hist->retransform();
 			else {
 				//no sender available, the function was called in CartesianPlot::dataChanged() (live data source got new data)
 				//-> retransform all available curves since we don't know which curves are affected.
 				//TODO: this logic can be very expensive
 				for (auto* c : children<XYCurve>())
 					c->retransform();
 			}
 		}
 	}
 }
 
 /*!
 	called when in one of the curves the x-data was changed.
 	Autoscales the coordinate system and the x-axes, when "auto-scale" is active.
 */
 void CartesianPlot::xDataChanged() {
 	if (project()->isLoading())
 		return;
 
 	Q_D(CartesianPlot);
 	if (d->suppressRetransform)
 		return;
 
 	d->curvesXMinMaxIsDirty = true;
 	if (d->autoScaleX)
 		this->scaleAutoX();
 	else {
 		auto* curve = dynamic_cast<XYCurve*>(QObject::sender());
 		curve->retransform();
 	}
 
 	//in case there is only one curve and its column mode was changed, check whether we start plotting datetime data
 	if (children<XYCurve>().size() == 1) {
 		auto* curve = dynamic_cast<XYCurve*>(QObject::sender());
 		const AbstractColumn* col = curve->xColumn();
 		if (col->columnMode() == AbstractColumn::DateTime && d->xRangeFormat != CartesianPlot::DateTime) {
 			setUndoAware(false);
 			setXRangeFormat(CartesianPlot::DateTime);
 			setUndoAware(true);
 		}
 	}
 }
 
 /*!
 	called when in one of the curves the x-data was changed.
 	Autoscales the coordinate system and the x-axes, when "auto-scale" is active.
 */
 void CartesianPlot::yDataChanged() {
 	if (project()->isLoading())
 		return;
 
 	Q_D(CartesianPlot);
 	if (d->suppressRetransform)
 		return;
 
 	d->curvesYMinMaxIsDirty = true;
 	if (d->autoScaleY)
 		this->scaleAutoY();
 	else {
 		auto* curve = dynamic_cast<XYCurve*>(QObject::sender());
 		curve->retransform();
 	}
 
 	//in case there is only one curve and its column mode was changed, check whether we start plotting datetime data
 	if (children<XYCurve>().size() == 1) {
 		auto* curve = dynamic_cast<XYCurve*>(QObject::sender());
 		const AbstractColumn* col = curve->yColumn();
 		if (col->columnMode() == AbstractColumn::DateTime && d->xRangeFormat != CartesianPlot::DateTime) {
 			setUndoAware(false);
 			setYRangeFormat(CartesianPlot::DateTime);
 			setUndoAware(true);
 		}
 	}
 }
 
 void CartesianPlot::curveVisibilityChanged() {
 	Q_D(CartesianPlot);
 	d->curvesXMinMaxIsDirty = true;
 	d->curvesYMinMaxIsDirty = true;
 	updateLegend();
 	if (d->autoScaleX && d->autoScaleY)
 		this->scaleAuto();
 	else if (d->autoScaleX)
 		this->scaleAutoX();
 	else if (d->autoScaleY)
 		this->scaleAutoY();
 }
 
 void CartesianPlot::setMouseMode(const MouseMode mouseMode) {
 	Q_D(CartesianPlot);
 
 	d->mouseMode = mouseMode;
 	d->setHandlesChildEvents(mouseMode != CartesianPlot::SelectionMode);
 
 	QList<QGraphicsItem*> items = d->childItems();
 	if (d->mouseMode == CartesianPlot::SelectionMode) {
 		for (auto* item : items)
 			item->setFlag(QGraphicsItem::ItemStacksBehindParent, false);
 	} else {
 		for (auto* item : items)
 			item->setFlag(QGraphicsItem::ItemStacksBehindParent, true);
 	}
 
 	//when doing zoom selection, prevent the graphics item from being movable
 	//if it's currently movable (no worksheet layout available)
 	const auto* worksheet = dynamic_cast<const Worksheet*>(parentAspect());
 	if (worksheet) {
 		if (mouseMode == CartesianPlot::SelectionMode) {
 			if (worksheet->layout() != Worksheet::NoLayout)
 				graphicsItem()->setFlag(QGraphicsItem::ItemIsMovable, false);
 			else
 				graphicsItem()->setFlag(QGraphicsItem::ItemIsMovable, true);
 		} else   //zoom m_selection
 			graphicsItem()->setFlag(QGraphicsItem::ItemIsMovable, false);
 	}
 }
 
 void CartesianPlot::setLocked(bool locked) {
 	Q_D(CartesianPlot);
 	d->locked = locked;
 }
 
 void CartesianPlot::scaleAutoX() {
 	Q_D(CartesianPlot);
 	if (d->curvesXMinMaxIsDirty) {
 		int count = 0;
 		switch (d->rangeType) {
 		case CartesianPlot::RangeFree:
 			count = 0;
 			break;
 		case CartesianPlot::RangeLast:
 			count = -d->rangeLastValues;
 			break;
 		case CartesianPlot::RangeFirst:
 			count = d->rangeFirstValues;
 			break;
 		}
 
 		d->curvesXMin = INFINITY;
 		d->curvesXMax = -INFINITY;
 
 		//loop over all xy-curves and determine the maximum and minimum x-values
 		for (const auto* curve : this->children<const XYCurve>()) {
 			if (!curve->isVisible())
 				continue;
 			if (!curve->xColumn())
 				continue;
 
 			const double min = curve->xColumn()->minimum(count);
 			if (min < d->curvesXMin)
 				d->curvesXMin = min;
 
 			const double max = curve->xColumn()->maximum(count);
 			if (max > d->curvesXMax)
 				d->curvesXMax = max;
 		}
 
 		//loop over all histograms and determine the maximum and minimum x-values
 		for (const auto* curve : this->children<const Histogram>()) {
 			if (!curve->isVisible())
 				continue;
 			if (!curve->dataColumn())
 				continue;
 
 			const double min = curve->getXMinimum();
 			if (d->curvesXMin > min)
 				d->curvesXMin = min;
 
 			const double max = curve->getXMaximum();
 			if (max > d->curvesXMax)
 				d->curvesXMax = max;
 		}
 
 		d->curvesXMinMaxIsDirty = false;
 	}
 
 	bool update = false;
 	if (d->curvesXMin != d->xMin && d->curvesXMin != INFINITY) {
 		d->xMin = d->curvesXMin;
 		update = true;
 	}
 
 	if (d->curvesXMax != d->xMax && d->curvesXMax != -INFINITY) {
 		d->xMax = d->curvesXMax;
 		update = true;
 	}
 
 	if (update) {
 		if (d->xMax == d->xMin) {
 			//in case min and max are equal (e.g. if we plot a single point), subtract/add 10% of the value
 			if (d->xMax != 0) {
 				d->xMax = d->xMax*1.1;
 				d->xMin = d->xMin*0.9;
 			} else {
 				d->xMax = 0.1;
 				d->xMin = -0.1;
 			}
 		} else {
 			double offset = (d->xMax - d->xMin)*d->autoScaleOffsetFactor;
 			d->xMin -= offset;
 			d->xMax += offset;
 		}
 		d->retransformScales();
 	}
 }
 
 void CartesianPlot::scaleAutoY() {
 	Q_D(CartesianPlot);
 
 	if (d->curvesYMinMaxIsDirty) {
 		int count = 0;
 		switch (d->rangeType) {
 		case CartesianPlot::RangeFree:
 			count = 0;
 			break;
 		case CartesianPlot::RangeLast:
 			count = -d->rangeLastValues;
 			break;
 		case CartesianPlot::RangeFirst:
 			count = d->rangeFirstValues;
 			break;
 		}
 
 		d->curvesYMin = INFINITY;
 		d->curvesYMax = -INFINITY;
 
 		//loop over all xy-curves and determine the maximum and minimum y-values
 		for (const auto* curve : this->children<const XYCurve>()) {
 			if (!curve->isVisible())
 				continue;
 			if (!curve->yColumn())
 				continue;
 
 			const double min = curve->yColumn()->minimum(count);
 			if (min < d->curvesYMin)
 				d->curvesYMin = min;
 
 			const double max = curve->yColumn()->maximum(count);
 			if (max > d->curvesYMax)
 				d->curvesYMax = max;
 		}
 
 		//loop over all histograms and determine the maximum y-value
 		for (const auto* curve : this->children<const Histogram>()) {
 			if (!curve->isVisible())
 				continue;
 
 			const double min = curve->getYMinimum();
 			if (d->curvesYMin > min)
 				d->curvesYMin = min;
 
 			const double max = curve->getYMaximum();
 			if (max > d->curvesYMax)
 				d->curvesYMax = max;
 		}
 
 		d->curvesYMinMaxIsDirty = false;
 	}
 
 
 	bool update = false;
 	if (d->curvesYMin != d->yMin && d->curvesYMin != INFINITY) {
 		d->yMin = d->curvesYMin;
 		update = true;
 	}
 
 	if (d->curvesYMax != d->yMax && d->curvesYMax != -INFINITY) {
 		d->yMax = d->curvesYMax;
 		update = true;
 	}
 	if (update) {
 		if (d->yMax == d->yMin) {
 			//in case min and max are equal (e.g. if we plot a single point), subtract/add 10% of the value
 			if (d->yMax != 0) {
 				d->yMax = d->yMax*1.1;
 				d->yMin = d->yMin*0.9;
 			} else {
 				d->yMax = 0.1;
 				d->yMin = -0.1;
 			}
 		} else {
 			double offset = (d->yMax - d->yMin)*d->autoScaleOffsetFactor;
 			d->yMin -= offset;
 			d->yMax += offset;
 		}
 		d->retransformScales();
 	}
 }
 
 void CartesianPlot::scaleAuto() {
 	DEBUG("CartesianPlot::scaleAuto()");
 	Q_D(CartesianPlot);
 
 	int count = 0;
 	switch (d->rangeType) {
 	case CartesianPlot::RangeFree:
 		count = 0;
 		break;
 	case CartesianPlot::RangeLast:
 		count = -d->rangeLastValues;
 		break;
 	case CartesianPlot::RangeFirst:
 		count = d->rangeFirstValues;
 		break;
 	}
 
 	if (d->curvesXMinMaxIsDirty) {
 		d->curvesXMin = INFINITY;
 		d->curvesXMax = -INFINITY;
 
 		//loop over all xy-curves and determine the maximum and minimum x-values
 		for (const auto* curve : this->children<const XYCurve>()) {
 			if (!curve->isVisible())
 				continue;
 			if (!curve->xColumn())
 				continue;
 
 			const double min = curve->xColumn()->minimum(count);
 			if (min < d->curvesXMin)
 				d->curvesXMin = min;
 
 			double max = curve->xColumn()->maximum(count);
 			if (max > d->curvesXMax)
 				d->curvesXMax = max;
 		}
 
 		//loop over all histograms and determine the maximum and minimum x-values
 		for (const auto* curve : this->children<const Histogram>()) {
 			if (!curve->isVisible())
 				continue;
 			if (!curve->dataColumn())
 				continue;
 
 			const double min = curve->getXMinimum();
 			if (d->curvesXMin > min)
 				d->curvesXMin = min;
 
 			const double max = curve->getXMaximum();
 			if (max > d->curvesXMax)
 				d->curvesXMax = max;
 
 		}
 
 		d->curvesXMinMaxIsDirty = false;
 	}
 
 	if (d->curvesYMinMaxIsDirty) {
 		d->curvesYMin = INFINITY;
 		d->curvesYMax = -INFINITY;
 
 		//loop over all xy-curves and determine the maximum and minimum y-values
 		for (const auto* curve : this->children<const XYCurve>()) {
 			if (!curve->isVisible())
 				continue;
 			if (!curve->yColumn())
 				continue;
 
 			const double min = curve->yColumn()->minimum(count);
 			if (min < d->curvesYMin)
 				d->curvesYMin = min;
 
 			const double max = curve->yColumn()->maximum(count);
 			if (max > d->curvesYMax)
 				d->curvesYMax = max;
 		}
 
 		//loop over all histograms and determine the maximum y-value
 		for (const auto* curve : this->children<const Histogram>()) {
 			if (!curve->isVisible())
 				continue;
 
 			const double min = curve->getYMinimum();
 			if (d->curvesYMin > min)
 				d->curvesYMin = min;
 
 			const double max = curve->getYMaximum();
 			if (max > d->curvesYMax)
 				d->curvesYMax = max;
 		}
 	}
 
 	bool updateX = false;
 	bool updateY = false;
 	if (d->curvesXMin != d->xMin && d->curvesXMin != INFINITY) {
 		d->xMin = d->curvesXMin;
 		updateX = true;
 	}
 
 	if (d->curvesXMax != d->xMax && d->curvesXMax != -INFINITY) {
 		d->xMax = d->curvesXMax;
 		updateX = true;
 	}
 
 	if (d->curvesYMin != d->yMin && d->curvesYMin != INFINITY) {
 		d->yMin = d->curvesYMin;
 		updateY = true;
 	}
 
 	if (d->curvesYMax != d->yMax && d->curvesYMax != -INFINITY) {
 		d->yMax = d->curvesYMax;
 		updateY = true;
 	}
 	DEBUG(" xmin/xmax = " << d->xMin << '/' << d->xMax << ", ymin/ymax = " << d->yMin << '/' << d->yMax);
 
 	if (updateX || updateY) {
 		if (updateX) {
 			if (d->xMax == d->xMin) {
 				//in case min and max are equal (e.g. if we plot a single point), subtract/add 10% of the value
 				if (d->xMax != 0) {
 					d->xMax = d->xMax*1.1;
 					d->xMin = d->xMin*0.9;
 				} else {
 					d->xMax = 0.1;
 					d->xMin = -0.1;
 				}
 			} else {
 				double offset = (d->xMax - d->xMin)*d->autoScaleOffsetFactor;
 				d->xMin -= offset;
 				d->xMax += offset;
 			}
 		}
 		if (updateY) {
 			if (d->yMax == d->yMin) {
 				//in case min and max are equal (e.g. if we plot a single point), subtract/add 10% of the value
 				if (d->yMax != 0) {
 					d->yMax = d->yMax*1.1;
 					d->yMin = d->yMin*0.9;
 				} else {
 					d->yMax = 0.1;
 					d->yMin = -0.1;
 				}
 			} else {
 				double offset = (d->yMax - d->yMin)*d->autoScaleOffsetFactor;
 				d->yMin -= offset;
 				d->yMax += offset;
 			}
 		}
 		d->retransformScales();
 	}
 }
 
 void CartesianPlot::zoomIn() {
 	Q_D(CartesianPlot);
 
 	double oldRange = (d->xMax - d->xMin);
 	double newRange = (d->xMax - d->xMin) / m_zoomFactor;
 	d->xMax = d->xMax + (newRange - oldRange) / 2;
 	d->xMin = d->xMin - (newRange - oldRange) / 2;
 
 	oldRange = (d->yMax - d->yMin);
 	newRange = (d->yMax - d->yMin) / m_zoomFactor;
 	d->yMax = d->yMax + (newRange - oldRange) / 2;
 	d->yMin = d->yMin - (newRange - oldRange) / 2;
 
 	d->retransformScales();
 }
 
 void CartesianPlot::zoomOut() {
 	Q_D(CartesianPlot);
 	double oldRange = (d->xMax-d->xMin);
 	double newRange = (d->xMax-d->xMin)*m_zoomFactor;
 	d->xMax = d->xMax + (newRange-oldRange)/2;
 	d->xMin = d->xMin - (newRange-oldRange)/2;
 
 	oldRange = (d->yMax-d->yMin);
 	newRange = (d->yMax-d->yMin)*m_zoomFactor;
 	d->yMax = d->yMax + (newRange-oldRange)/2;
 	d->yMin = d->yMin - (newRange-oldRange)/2;
 
 	d->retransformScales();
 }
 
 void CartesianPlot::zoomInX() {
 	Q_D(CartesianPlot);
 	double oldRange = (d->xMax-d->xMin);
 	double newRange = (d->xMax-d->xMin)/m_zoomFactor;
 	d->xMax = d->xMax + (newRange-oldRange)/2;
 	d->xMin = d->xMin - (newRange-oldRange)/2;
 	d->retransformScales();
 }
 
 void CartesianPlot::zoomOutX() {
 	Q_D(CartesianPlot);
 	double oldRange = (d->xMax-d->xMin);
 	double newRange = (d->xMax-d->xMin)*m_zoomFactor;
 	d->xMax = d->xMax + (newRange-oldRange)/2;
 	d->xMin = d->xMin - (newRange-oldRange)/2;
 	d->retransformScales();
 }
 
 void CartesianPlot::zoomInY() {
 	Q_D(CartesianPlot);
 	double oldRange = (d->yMax-d->yMin);
 	double newRange = (d->yMax-d->yMin)/m_zoomFactor;
 	d->yMax = d->yMax + (newRange-oldRange)/2;
 	d->yMin = d->yMin - (newRange-oldRange)/2;
 	d->retransformScales();
 }
 
 void CartesianPlot::zoomOutY() {
 	Q_D(CartesianPlot);
 	double oldRange = (d->yMax-d->yMin);
 	double newRange = (d->yMax-d->yMin)*m_zoomFactor;
 	d->yMax = d->yMax + (newRange-oldRange)/2;
 	d->yMin = d->yMin - (newRange-oldRange)/2;
 	d->retransformScales();
 }
 
 void CartesianPlot::shiftLeftX() {
 	Q_D(CartesianPlot);
 	double offsetX = (d->xMax-d->xMin)*0.1;
 	d->xMax -= offsetX;
 	d->xMin -= offsetX;
 	d->retransformScales();
 }
 
 void CartesianPlot::shiftRightX() {
 	Q_D(CartesianPlot);
 	double offsetX = (d->xMax-d->xMin)*0.1;
 	d->xMax += offsetX;
 	d->xMin += offsetX;
 	d->retransformScales();
 }
 
 void CartesianPlot::shiftUpY() {
 	Q_D(CartesianPlot);
 	double offsetY = (d->yMax-d->yMin)*0.1;
 	d->yMax += offsetY;
 	d->yMin += offsetY;
 	d->retransformScales();
 }
 
 void CartesianPlot::shiftDownY() {
 	Q_D(CartesianPlot);
 	double offsetY = (d->yMax-d->yMin)*0.1;
 	d->yMax -= offsetY;
 	d->yMin -= offsetY;
 	d->retransformScales();
 }
 
 //##############################################################################
 //######  SLOTs for changes triggered via QActions in the context menu  ########
 //##############################################################################
 void CartesianPlot::visibilityChanged() {
 	Q_D(CartesianPlot);
 	this->setVisible(!d->isVisible());
 }
 
 //#####################################################################
 //################### Private implementation ##########################
 //#####################################################################
 CartesianPlotPrivate::CartesianPlotPrivate(CartesianPlot* plot) : AbstractPlotPrivate(plot), q(plot) {
 	setData(0, WorksheetElement::NameCartesianPlot);
 }
 
 /*!
 	updates the position of plot rectangular in scene coordinates to \c r and recalculates the scales.
 	The size of the plot corresponds to the size of the plot area, the area which is filled with the background color etc.
 	and which can pose the parent item for several sub-items (like TextLabel).
 	Note, the size of the area used to define the coordinate system doesn't need to be equal to this plot area.
 	Also, the size (=bounding box) of CartesianPlot can be greater than the size of the plot area.
  */
 void CartesianPlotPrivate::retransform() {
 	if (suppressRetransform)
 		return;
 
 	PERFTRACE("CartesianPlotPrivate::retransform()");
 	prepareGeometryChange();
 	setPos( rect.x()+rect.width()/2, rect.y()+rect.height()/2);
 
 	updateDataRect();
 	retransformScales();
 
 	//plotArea position is always (0, 0) in parent's coordinates, don't need to update here
 	q->plotArea()->setRect(rect);
 
 	//call retransform() for the title and the legend (if available)
 	//when a predefined position relative to the (Left, Centered etc.) is used,
 	//the actual position needs to be updated on plot's geometry changes.
 	if (q->title())
 		q->title()->retransform();
 	if (q->m_legend)
 		q->m_legend->retransform();
 
 	WorksheetElementContainerPrivate::recalcShapeAndBoundingRect();
 }
 
 void CartesianPlotPrivate::retransformScales() {
 	PERFTRACE("CartesianPlotPrivate::retransformScales()");
 	DEBUG(" xmin/xmax = " << xMin << '/'<< xMax << ", ymin/ymax = " << yMin << '/' << yMax);
 
 	auto* plot = dynamic_cast<CartesianPlot*>(q);
 	QVector<CartesianScale*> scales;
 
 	//perform the mapping from the scene coordinates to the plot's coordinates here.
 	QRectF itemRect = mapRectFromScene(rect);
 
 	//check ranges for log-scales
 	if (xScale != CartesianPlot::ScaleLinear)
 		checkXRange();
 
 	//check whether we have x-range breaks - the first break, if available, should be valid
 	bool hasValidBreak = (xRangeBreakingEnabled && !xRangeBreaks.list.isEmpty() && xRangeBreaks.list.first().isValid());
 
 	static const int breakGap = 20;
 	double sceneStart, sceneEnd, logicalStart, logicalEnd;
 
 	//create x-scales
 	int plotSceneStart = itemRect.x() + horizontalPadding;
 	int plotSceneEnd = itemRect.x() + itemRect.width() - horizontalPadding;
 	if (!hasValidBreak) {
 		//no breaks available -> range goes from the plot beginning to the end of the plot
 		sceneStart = plotSceneStart;
 		sceneEnd = plotSceneEnd;
 		logicalStart = xMin;
 		logicalEnd = xMax;
 
 		//TODO: how should we handle the case sceneStart == sceneEnd?
 		//(to reproduce, create plots and adjust the spacing/pading to get zero size for the plots)
 		if (sceneStart != sceneEnd)
 			scales << this->createScale(xScale, sceneStart, sceneEnd, logicalStart, logicalEnd);
 	} else {
 		int sceneEndLast = plotSceneStart;
 		int logicalEndLast = xMin;
 		for (const auto& rb : xRangeBreaks.list) {
 			if (!rb.isValid())
 				break;
 
 			//current range goes from the end of the previous one (or from the plot beginning) to curBreak.start
 			sceneStart = sceneEndLast;
 			if (&rb == &xRangeBreaks.list.first()) sceneStart += breakGap;
 			sceneEnd = plotSceneStart + (plotSceneEnd-plotSceneStart) * rb.position;
 			logicalStart = logicalEndLast;
 			logicalEnd = rb.start;
 
 			if (sceneStart != sceneEnd)
 				scales << this->createScale(xScale, sceneStart, sceneEnd, logicalStart, logicalEnd);
 
 			sceneEndLast = sceneEnd;
 			logicalEndLast = rb.end;
 		}
 
 		//add the remaining range going from the last available range break to the end of the plot (=end of the x-data range)
 		sceneStart = sceneEndLast+breakGap;
 		sceneEnd = plotSceneEnd;
 		logicalStart = logicalEndLast;
 		logicalEnd = xMax;
 
 		if (sceneStart != sceneEnd)
 			scales << this->createScale(xScale, sceneStart, sceneEnd, logicalStart, logicalEnd);
 	}
 
 	cSystem->setXScales(scales);
 
 	//check ranges for log-scales
 	if (yScale != CartesianPlot::ScaleLinear)
 		checkYRange();
 
 	//check whether we have y-range breaks - the first break, if available, should be valid
 	hasValidBreak = (yRangeBreakingEnabled && !yRangeBreaks.list.isEmpty() && yRangeBreaks.list.first().isValid());
 
 	//create y-scales
 	scales.clear();
 	plotSceneStart = itemRect.y()+itemRect.height()-verticalPadding;
 	plotSceneEnd = itemRect.y()+verticalPadding;
 	if (!hasValidBreak) {
 		//no breaks available -> range goes from the plot beginning to the end of the plot
 		sceneStart = plotSceneStart;
 		sceneEnd = plotSceneEnd;
 		logicalStart = yMin;
 		logicalEnd = yMax;
 
 		if (sceneStart != sceneEnd)
 			scales << this->createScale(yScale, sceneStart, sceneEnd, logicalStart, logicalEnd);
 	} else {
 		int sceneEndLast = plotSceneStart;
 		int logicalEndLast = yMin;
 		for (const auto& rb : yRangeBreaks.list) {
 			if (!rb.isValid())
 				break;
 
 			//current range goes from the end of the previous one (or from the plot beginning) to curBreak.start
 			sceneStart = sceneEndLast;
 			if (&rb == &yRangeBreaks.list.first()) sceneStart -= breakGap;
 			sceneEnd = plotSceneStart + (plotSceneEnd-plotSceneStart) * rb.position;
 			logicalStart = logicalEndLast;
 			logicalEnd = rb.start;
 
 			if (sceneStart != sceneEnd)
 				scales << this->createScale(yScale, sceneStart, sceneEnd, logicalStart, logicalEnd);
 
 			sceneEndLast = sceneEnd;
 			logicalEndLast = rb.end;
 		}
 
 		//add the remaining range going from the last available range break to the end of the plot (=end of the y-data range)
 		sceneStart = sceneEndLast-breakGap;
 		sceneEnd = plotSceneEnd;
 		logicalStart = logicalEndLast;
 		logicalEnd = yMax;
 
 		if (sceneStart != sceneEnd)
 			scales << this->createScale(yScale, sceneStart, sceneEnd, logicalStart, logicalEnd);
 	}
 
 	cSystem->setYScales(scales);
 
 	//calculate the changes in x and y and save the current values for xMin, xMax, yMin, yMax
 	double deltaXMin = 0;
 	double deltaXMax = 0;
 	double deltaYMin = 0;
 	double deltaYMax = 0;
 
 	if (xMin != xMinPrev) {
 		deltaXMin = xMin - xMinPrev;
 		emit plot->xMinChanged(xMin);
 	}
 
 	if (xMax != xMaxPrev) {
 		deltaXMax = xMax - xMaxPrev;
 		emit plot->xMaxChanged(xMax);
 	}
 
 	if (yMin != yMinPrev) {
 		deltaYMin = yMin - yMinPrev;
 		emit plot->yMinChanged(yMin);
 	}
 
 	if (yMax != yMaxPrev) {
 		deltaYMax = yMax - yMaxPrev;
 		emit plot->yMaxChanged(yMax);
 	}
 
 	xMinPrev = xMin;
 	xMaxPrev = xMax;
 	yMinPrev = yMin;
 	yMaxPrev = yMax;
 	//adjust auto-scale axes
 	for (auto* axis : q->children<Axis>()) {
 		if (!axis->autoScale())
 			continue;
 
 		if (axis->orientation() == Axis::AxisHorizontal) {
 			if (deltaXMax != 0) {
 				axis->setUndoAware(false);
 				axis->setSuppressRetransform(true);
 				axis->setEnd(xMax);
 				axis->setUndoAware(true);
 				axis->setSuppressRetransform(false);
 			}
 			if (deltaXMin != 0) {
 				axis->setUndoAware(false);
 				axis->setSuppressRetransform(true);
 				axis->setStart(xMin);
 				axis->setUndoAware(true);
 				axis->setSuppressRetransform(false);
 			}
 			//TODO;
 // 			if (axis->position() == Axis::AxisCustom && deltaYMin != 0) {
 // 				axis->setOffset(axis->offset() + deltaYMin, false);
 // 			}
 		} else {
 			if (deltaYMax != 0) {
 				axis->setUndoAware(false);
 				axis->setSuppressRetransform(true);
 				axis->setEnd(yMax);
 				axis->setUndoAware(true);
 				axis->setSuppressRetransform(false);
 			}
 			if (deltaYMin != 0) {
 				axis->setUndoAware(false);
 				axis->setSuppressRetransform(true);
 				axis->setStart(yMin);
 				axis->setUndoAware(true);
 				axis->setSuppressRetransform(false);
 			}
 
 			//TODO;
 // 			if (axis->position() == Axis::AxisCustom && deltaXMin != 0) {
 // 				axis->setOffset(axis->offset() + deltaXMin, false);
 // 			}
 		}
 	}
 	// call retransform() on the parent to trigger the update of all axes and curvesю
 	//no need to do this on load since all plots are retransformed again after the project is loaded.
 	if (!q->isLoading())
 		q->retransform();
 }
 
 /*
  * calculates the rectangular of the are showing the actual data (plot's rect minus padding),
  * in plot's coordinates.
  */
 void CartesianPlotPrivate::updateDataRect() {
 	dataRect = mapRectFromScene(rect);
 	dataRect.setX(dataRect.x() + horizontalPadding);
 	dataRect.setY(dataRect.y() + verticalPadding);
 	dataRect.setWidth(dataRect.width() - horizontalPadding);
 	dataRect.setHeight(dataRect.height() - verticalPadding);
 }
 
 void CartesianPlotPrivate::rangeChanged() {
 	curvesXMinMaxIsDirty = true;
 	curvesYMinMaxIsDirty = true;
 	if (autoScaleX && autoScaleY)
 		q->scaleAuto();
 	else if (autoScaleX)
 		q->scaleAutoX();
 	else if (autoScaleY)
 		q->scaleAutoY();
 }
 
 void CartesianPlotPrivate::xRangeFormatChanged() {
 	for (auto* axis : q->children<Axis>()) {
 		if (axis->orientation() == Axis::AxisHorizontal)
 			axis->retransformTickLabelStrings();
 	}
 }
 
 void CartesianPlotPrivate::yRangeFormatChanged() {
 	for (auto* axis : q->children<Axis>()) {
 		if (axis->orientation() == Axis::AxisVertical)
 			axis->retransformTickLabelStrings();
 	}
 }
 
 /*!
  * don't allow any negative values for the x range when log or sqrt scalings are used
  */
 void CartesianPlotPrivate::checkXRange() {
 	double min = 0.01;
 
 	if (xMin <= 0.0) {
 		(min < xMax*min) ? xMin = min : xMin = xMax*min;
 		emit q->xMinChanged(xMin);
 	} else if (xMax <= 0.0) {
 		(-min > xMin*min) ? xMax = -min : xMax = xMin*min;
 		emit q->xMaxChanged(xMax);
 	}
 }
 
 /*!
  * don't allow any negative values for the y range when log or sqrt scalings are used
  */
 void CartesianPlotPrivate::checkYRange() {
 	double min = 0.01;
 
 	if (yMin <= 0.0) {
 		(min < yMax*min) ? yMin = min : yMin = yMax*min;
 		emit q->yMinChanged(yMin);
 	} else if (yMax <= 0.0) {
 		(-min > yMin*min) ? yMax = -min : yMax = yMin*min;
 		emit q->yMaxChanged(yMax);
 	}
 }
 
 CartesianScale* CartesianPlotPrivate::createScale(CartesianPlot::Scale type, double sceneStart, double sceneEnd, double logicalStart, double logicalEnd) {
 	DEBUG("CartesianPlotPrivate::createScale() scene start/end = " << sceneStart << '/' << sceneEnd << ", logical start/end = " << logicalStart << '/' << logicalEnd);
 // 	Interval<double> interval (logicalStart-0.01, logicalEnd+0.01); //TODO: move this to CartesianScale
 	Interval<double> interval (std::numeric_limits<double>::lowest(), std::numeric_limits<double>::max());
 // 	Interval<double> interval (logicalStart, logicalEnd);
 	if (type == CartesianPlot::ScaleLinear)
 		return CartesianScale::createLinearScale(interval, sceneStart, sceneEnd, logicalStart, logicalEnd);
 	else {
 		double base;
 		if (type == CartesianPlot::ScaleLog10)
 			base = 10.0;
 		else if (type == CartesianPlot::ScaleLog2)
 			base = 2.0;
 		else
 			base = M_E;
 
 		return CartesianScale::createLogScale(interval, sceneStart, sceneEnd, logicalStart, logicalEnd, base);
 	}
 }
 
 /*!
  * Reimplemented from QGraphicsItem.
  */
 QVariant CartesianPlotPrivate::itemChange(GraphicsItemChange change, const QVariant &value) {
 	if (change == QGraphicsItem::ItemPositionChange) {
 		const QPointF& itemPos = value.toPointF();//item's center point in parent's coordinates;
 		const qreal x = itemPos.x();
 		const qreal y = itemPos.y();
 
 		//calculate the new rect and forward the changes to the frontend
 		QRectF newRect;
 		const qreal w = rect.width();
 		const qreal h = rect.height();
 		newRect.setX(x-w/2);
 		newRect.setY(y-h/2);
 		newRect.setWidth(w);
 		newRect.setHeight(h);
 		emit q->rectChanged(newRect);
 	}
 	return QGraphicsItem::itemChange(change, value);
 }
 
 //##############################################################################
 //##################################  Events  ##################################
 //##############################################################################
 void CartesianPlotPrivate::mousePressEvent(QGraphicsSceneMouseEvent *event) {
 	if (mouseMode == CartesianPlot::ZoomSelectionMode || mouseMode == CartesianPlot::ZoomXSelectionMode || mouseMode == CartesianPlot::ZoomYSelectionMode) {
 
 		if (mouseMode == CartesianPlot::ZoomSelectionMode)
 			m_selectionStart = event->pos();
 		else if (mouseMode == CartesianPlot::ZoomXSelectionMode) {
 			m_selectionStart.setX(event->pos().x());
 			m_selectionStart.setY(dataRect.height()/2);
 		} else if (mouseMode == CartesianPlot::ZoomYSelectionMode) {
 			m_selectionStart.setX(-dataRect.width()/2);
 			m_selectionStart.setY(event->pos().y());
 		}
 
 		m_selectionEnd = m_selectionStart;
 		m_selectionBandIsShown = true;
 	} else {
 		if (!locked && dataRect.contains(event->pos()) ){
 			panningStarted = true;
 			m_panningStart = event->pos();
 			setCursor(Qt::ClosedHandCursor);
 		}
 		QGraphicsItem::mousePressEvent(event);
 	}
 }
 
 void CartesianPlotPrivate::mouseMoveEvent(QGraphicsSceneMouseEvent* event) {
 	if (mouseMode == CartesianPlot::SelectionMode) {
 		if (panningStarted && dataRect.contains(event->pos()) ) {
 			//don't retransform on small mouse movement deltas
 			const int deltaXScene = (m_panningStart.x() - event->pos().x());
 			const int deltaYScene = (m_panningStart.y() - event->pos().y());
 			if (abs(deltaXScene) < 5 && abs(deltaYScene) < 5)
 				return;
 
 			const QPointF logicalEnd = cSystem->mapSceneToLogical(event->pos());
 			const QPointF logicalStart = cSystem->mapSceneToLogical(m_panningStart);
 			const float deltaX = (logicalStart.x() - logicalEnd.x());
 			const float deltaY = (logicalStart.y() - logicalEnd.y());
 			xMax += deltaX;
 			xMin += deltaX;
 			yMax += deltaY;
 			yMin += deltaY;
 			retransformScales();
 			m_panningStart = event->pos();
 		} else
 			QGraphicsItem::mouseMoveEvent(event);
 	} else if (mouseMode == CartesianPlot::ZoomSelectionMode || mouseMode == CartesianPlot::ZoomXSelectionMode || mouseMode == CartesianPlot::ZoomYSelectionMode) {
 		QGraphicsItem::mouseMoveEvent(event);
 		if ( !boundingRect().contains(event->pos()) ) {
 			q->info("");
 			return;
 		}
 
 		QString info;
 		QPointF logicalStart = cSystem->mapSceneToLogical(m_selectionStart);
 		if (mouseMode == CartesianPlot::ZoomSelectionMode) {
 			m_selectionEnd = event->pos();
 			QPointF logicalEnd = cSystem->mapSceneToLogical(m_selectionEnd);
 			if (xRangeFormat == CartesianPlot::Numeric)
 				 info = QString::fromUtf8("Δx=") + QString::number(logicalEnd.x()-logicalStart.x());
 			else
 				info = i18n("from x=%1 to x=%2", QDateTime::fromMSecsSinceEpoch(logicalStart.x()).toString(xRangeDateTimeFormat),
 													QDateTime::fromMSecsSinceEpoch(logicalEnd.x()).toString(xRangeDateTimeFormat));
 
 			info += QLatin1String(", ");
 			if (yRangeFormat == CartesianPlot::Numeric)
 				 info += QString::fromUtf8("Δy=") + QString::number(logicalEnd.y()-logicalStart.y());
 			else
 				info += i18n("from y=%1 to y=%2", QDateTime::fromMSecsSinceEpoch(logicalStart.y()).toString(xRangeDateTimeFormat),
 													QDateTime::fromMSecsSinceEpoch(logicalEnd.y()).toString(xRangeDateTimeFormat));
 		} else if (mouseMode == CartesianPlot::ZoomXSelectionMode) {
 			m_selectionEnd.setX(event->pos().x());
 			m_selectionEnd.setY(-dataRect.height()/2);
 			QPointF logicalEnd = cSystem->mapSceneToLogical(m_selectionEnd);
 			if (xRangeFormat == CartesianPlot::Numeric)
 				 info = QString::fromUtf8("Δx=") + QString::number(logicalEnd.x()-logicalStart.x());
 			else
 				info = i18n("from x=%1 to x=%2", QDateTime::fromMSecsSinceEpoch(logicalStart.x()).toString(xRangeDateTimeFormat),
 													QDateTime::fromMSecsSinceEpoch(logicalEnd.x()).toString(xRangeDateTimeFormat));
 		} else if (mouseMode == CartesianPlot::ZoomYSelectionMode) {
 			m_selectionEnd.setX(dataRect.width()/2);
 			m_selectionEnd.setY(event->pos().y());
 			QPointF logicalEnd = cSystem->mapSceneToLogical(m_selectionEnd);
 			if (yRangeFormat == CartesianPlot::Numeric)
 				 info = QString::fromUtf8("Δy=") + QString::number(logicalEnd.y()-logicalStart.y());
 			else
 				info = i18n("from y=%1 to y=%2", QDateTime::fromMSecsSinceEpoch(logicalStart.y()).toString(xRangeDateTimeFormat),
 													QDateTime::fromMSecsSinceEpoch(logicalEnd.y()).toString(xRangeDateTimeFormat));
 		}
 		q->info(info);
 		update();
 	}
 }
 
 void CartesianPlotPrivate::mouseReleaseEvent(QGraphicsSceneMouseEvent* event) {
 	setCursor(Qt::ArrowCursor);
 	if (mouseMode == CartesianPlot::SelectionMode) {
 		panningStarted = false;
 
 		//TODO: why do we do this all the time?!?!
 		const QPointF& itemPos = pos();//item's center point in parent's coordinates;
 		const qreal x = itemPos.x();
 		const qreal y = itemPos.y();
 
 		//calculate the new rect and set it
 		QRectF newRect;
 		const qreal w = rect.width();
 		const qreal h = rect.height();
 		newRect.setX(x-w/2);
 		newRect.setY(y-h/2);
 		newRect.setWidth(w);
 		newRect.setHeight(h);
 
 		suppressRetransform = true;
 		q->setRect(newRect);
 		suppressRetransform = false;
 
 		QGraphicsItem::mouseReleaseEvent(event);
 	} else if (mouseMode == CartesianPlot::ZoomSelectionMode || mouseMode == CartesianPlot::ZoomXSelectionMode || mouseMode == CartesianPlot::ZoomYSelectionMode) {
 		//don't zoom if very small region was selected, avoid occasional/unwanted zooming
 		if ( qAbs(m_selectionEnd.x()-m_selectionStart.x()) < 20 || qAbs(m_selectionEnd.y()-m_selectionStart.y()) < 20 ) {
 			m_selectionBandIsShown = false;
 			return;
 		}
 
 		//determine the new plot ranges
 		QPointF logicalZoomStart = cSystem->mapSceneToLogical(m_selectionStart, AbstractCoordinateSystem::SuppressPageClipping);
 		QPointF logicalZoomEnd = cSystem->mapSceneToLogical(m_selectionEnd, AbstractCoordinateSystem::SuppressPageClipping);
 		if (m_selectionEnd.x() > m_selectionStart.x()) {
 			xMin = logicalZoomStart.x();
 			xMax = logicalZoomEnd.x();
 		} else {
 			xMin = logicalZoomEnd.x();
 			xMax = logicalZoomStart.x();
 		}
 
 		if (m_selectionEnd.y() > m_selectionStart.y()) {
 			yMin = logicalZoomEnd.y();
 			yMax = logicalZoomStart.y();
 		} else {
 			yMin = logicalZoomStart.y();
 			yMax = logicalZoomEnd.y();
 		}
 
 		m_selectionBandIsShown = false;
 		retransformScales();
 	}
 }
 
 void CartesianPlotPrivate::wheelEvent(QGraphicsSceneWheelEvent* event) {
 	if (locked)
 		return;
 
 	//determine first, which axes are selected and zoom only in the corresponding direction.
 	//zoom the entire plot if no axes selected.
 	bool zoomX = false;
 	bool zoomY = false;
 	for (auto* axis : q->children<Axis>()) {
 		if (!axis->graphicsItem()->isSelected())
 			continue;
 
 		if (axis->orientation() == Axis::AxisHorizontal)
 			zoomX  = true;
 		else
 			zoomY = true;
 	}
 
 	if (event->delta() > 0) {
 		if (!zoomX && !zoomY) {
 			//no special axis selected -> zoom in everything
 			q->zoomIn();
 		} else {
 			if (zoomX) q->zoomInX();
 			if (zoomY) q->zoomInY();
 		}
 	} else {
 		if (!zoomX && !zoomY) {
 			//no special axis selected -> zoom in everything
 			q->zoomOut();
 		} else {
 			if (zoomX) q->zoomOutX();
 			if (zoomY) q->zoomOutY();
 		}
 	}
 }
 
 void CartesianPlotPrivate::hoverMoveEvent(QGraphicsSceneHoverEvent* event) {
 	QPointF point = event->pos();
 	QString info;
 	if (dataRect.contains(point)) {
 		QPointF logicalPoint = cSystem->mapSceneToLogical(point);
 		if (mouseMode == CartesianPlot::ZoomSelectionMode && !m_selectionBandIsShown) {
 			info = "x=";
 			if (xRangeFormat == CartesianPlot::Numeric)
 				 info += QString::number(logicalPoint.x());
 			else
 				info += QDateTime::fromMSecsSinceEpoch(logicalPoint.x()).toString(xRangeDateTimeFormat);
 
 			info += ", y=";
 			if (yRangeFormat == CartesianPlot::Numeric)
 				info += QString::number(logicalPoint.y());
 			else
 				info += QDateTime::fromMSecsSinceEpoch(logicalPoint.y()).toString(yRangeDateTimeFormat);
 		} else if (mouseMode == CartesianPlot::ZoomXSelectionMode && !m_selectionBandIsShown) {
 			QPointF p1(logicalPoint.x(), yMin);
 			QPointF p2(logicalPoint.x(), yMax);
 			m_selectionStartLine.setP1(cSystem->mapLogicalToScene(p1));
 			m_selectionStartLine.setP2(cSystem->mapLogicalToScene(p2));
 			info = "x=";
 			if (xRangeFormat == CartesianPlot::Numeric)
 				 info += QString::number(logicalPoint.x());
 			else
 				info += QDateTime::fromMSecsSinceEpoch(logicalPoint.x()).toString(xRangeDateTimeFormat);
 			update();
 		} else if (mouseMode == CartesianPlot::ZoomYSelectionMode && !m_selectionBandIsShown) {
 			QPointF p1(xMin, logicalPoint.y());
 			QPointF p2(xMax, logicalPoint.y());
 			m_selectionStartLine.setP1(cSystem->mapLogicalToScene(p1));
 			m_selectionStartLine.setP2(cSystem->mapLogicalToScene(p2));
 			info = "y=";
 			if (yRangeFormat == CartesianPlot::Numeric)
 				info += QString::number(logicalPoint.y());
 			else
 				info += QDateTime::fromMSecsSinceEpoch(logicalPoint.y()).toString(yRangeDateTimeFormat);
 			update();
 		}
 	}
 	q->info(info);
 
 	QGraphicsItem::hoverMoveEvent(event);
 }
 
 void CartesianPlotPrivate::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget * widget) {
 	if (!isVisible())
 		return;
 
 	painter->setPen(QPen(Qt::black, 3));
 	if ((mouseMode == CartesianPlot::ZoomXSelectionMode || mouseMode == CartesianPlot::ZoomYSelectionMode)
 	        && (!m_selectionBandIsShown))
 		painter->drawLine(m_selectionStartLine);
 
 	if (m_selectionBandIsShown) {
 		painter->save();
 		painter->setPen(QPen(Qt::black, 5));
 		painter->drawRect(QRectF(m_selectionStart, m_selectionEnd));
 		painter->setBrush(Qt::blue);
 		painter->setOpacity(0.2);
 		painter->drawRect(QRectF(m_selectionStart, m_selectionEnd));
 		painter->restore();
 	}
 
 	WorksheetElementContainerPrivate::paint(painter, option, widget);
 }
 
 //##############################################################################
 //##################  Serialization/Deserialization  ###########################
 //##############################################################################
 
 //! Save as XML
 void CartesianPlot::save(QXmlStreamWriter* writer) const {
 	Q_D(const CartesianPlot);
 
 	writer->writeStartElement( "cartesianPlot" );
 	writeBasicAttributes(writer);
 	writeCommentElement(writer);
 
 	//applied theme
 	if (!d->theme.isEmpty()) {
 		writer->writeStartElement( "theme" );
 		writer->writeAttribute("name", d->theme);
 		writer->writeEndElement();
 	}
 
 	//geometry
 	writer->writeStartElement( "geometry" );
 	writer->writeAttribute( "x", QString::number(d->rect.x()) );
 	writer->writeAttribute( "y", QString::number(d->rect.y()) );
 	writer->writeAttribute( "width", QString::number(d->rect.width()) );
 	writer->writeAttribute( "height", QString::number(d->rect.height()) );
 	writer->writeAttribute( "visible", QString::number(d->isVisible()) );
 	writer->writeEndElement();
 
 	//coordinate system and padding
 	writer->writeStartElement( "coordinateSystem" );
 	writer->writeAttribute( "autoScaleX", QString::number(d->autoScaleX) );
 	writer->writeAttribute( "autoScaleY", QString::number(d->autoScaleY) );
 	writer->writeAttribute( "xMin", QString::number(d->xMin, 'g', 16));
 	writer->writeAttribute( "xMax", QString::number(d->xMax, 'g', 16) );
 	writer->writeAttribute( "yMin", QString::number(d->yMin, 'g', 16) );
 	writer->writeAttribute( "yMax", QString::number(d->yMax, 'g', 16) );
 	writer->writeAttribute( "xScale", QString::number(d->xScale) );
 	writer->writeAttribute( "yScale", QString::number(d->yScale) );
 	writer->writeAttribute( "xRangeFormat", QString::number(d->xRangeFormat) );
 	writer->writeAttribute( "yRangeFormat", QString::number(d->yRangeFormat) );
 	writer->writeAttribute( "horizontalPadding", QString::number(d->horizontalPadding) );
 	writer->writeAttribute( "verticalPadding", QString::number(d->verticalPadding) );
 	writer->writeEndElement();
 
 	//x-scale breaks
 	if (d->xRangeBreakingEnabled || !d->xRangeBreaks.list.isEmpty()) {
 		writer->writeStartElement("xRangeBreaks");
 		writer->writeAttribute( "enabled", QString::number(d->xRangeBreakingEnabled) );
 		for (const auto& rb : d->xRangeBreaks.list) {
 			writer->writeStartElement("xRangeBreak");
 			writer->writeAttribute("start", QString::number(rb.start));
 			writer->writeAttribute("end", QString::number(rb.end));
 			writer->writeAttribute("position", QString::number(rb.position));
 			writer->writeAttribute("style", QString::number(rb.style));
 			writer->writeEndElement();
 		}
 		writer->writeEndElement();
 	}
 
 	//y-scale breaks
 	if (d->yRangeBreakingEnabled || !d->yRangeBreaks.list.isEmpty()) {
 		writer->writeStartElement("yRangeBreaks");
 		writer->writeAttribute( "enabled", QString::number(d->yRangeBreakingEnabled) );
 		for (const auto& rb : d->yRangeBreaks.list) {
 			writer->writeStartElement("yRangeBreak");
 			writer->writeAttribute("start", QString::number(rb.start));
 			writer->writeAttribute("end", QString::number(rb.end));
 			writer->writeAttribute("position", QString::number(rb.position));
 			writer->writeAttribute("style", QString::number(rb.style));
 			writer->writeEndElement();
 		}
 		writer->writeEndElement();
 	}
 
 	//serialize all children (plot area, title text label, axes and curves)
 	for (auto* elem : children<WorksheetElement>(IncludeHidden))
 		elem->save(writer);
 
 	writer->writeEndElement(); // close "cartesianPlot" section
 }
 
 
 //! Load from XML
 bool CartesianPlot::load(XmlStreamReader* reader, bool preview) {
 	Q_D(CartesianPlot);
 
 	if (!readBasicAttributes(reader))
 		return false;
 
 	KLocalizedString attributeWarning = ki18n("Attribute '%1' missing or empty, default value is used");
 	QXmlStreamAttributes attribs;
 	QString str;
 	bool titleLabelRead = false;
 
 	while (!reader->atEnd()) {
 		reader->readNext();
 		if (reader->isEndElement() && reader->name() == "cartesianPlot")
 			break;
 
 		if (!reader->isStartElement())
 			continue;
 
 		if (reader->name() == "comment") {
 			if (!readCommentElement(reader))
 				return false;
 		} else if (!preview && reader->name() == "theme") {
 			attribs = reader->attributes();
 			d->theme = attribs.value("name").toString();
 		} else if (!preview && reader->name() == "geometry") {
 			attribs = reader->attributes();
 
 			str = attribs.value("x").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("x").toString());
 			else
 				d->rect.setX( str.toDouble() );
 
 			str = attribs.value("y").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("y").toString());
 			else
 				d->rect.setY( str.toDouble() );
 
 			str = attribs.value("width").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("width").toString());
 			else
 				d->rect.setWidth( str.toDouble() );
 
 			str = attribs.value("height").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("height").toString());
 			else
 				d->rect.setHeight( str.toDouble() );
 
 			str = attribs.value("visible").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("visible").toString());
 			else
 				d->setVisible(str.toInt());
 		} else if (!preview && reader->name() == "coordinateSystem") {
 			attribs = reader->attributes();
 
 			READ_INT_VALUE("autoScaleX", autoScaleX, bool);
 			READ_INT_VALUE("autoScaleY", autoScaleY, bool);
 
 			str = attribs.value("xMin").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("xMin").toString());
 			else {
 				d->xMin = str.toDouble();
 				d->xMinPrev = d->xMin;
 			}
 
 			str = attribs.value("xMax").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("xMax").toString());
 			else {
 				d->xMax = str.toDouble();
 				d->xMaxPrev = d->xMax;
 			}
 
 			str = attribs.value("yMin").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("yMin").toString());
 			else {
 				d->yMin = str.toDouble();
 				d->yMinPrev = d->yMin;
 			}
 
 			str = attribs.value("yMax").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("yMax").toString());
 			else {
 				d->yMax = str.toDouble();
 				d->yMaxPrev = d->yMax;
 			}
 
 			READ_INT_VALUE("xScale", xScale, CartesianPlot::Scale);
 			READ_INT_VALUE("yScale", yScale, CartesianPlot::Scale);
 
 			READ_INT_VALUE("xRangeFormat", xRangeFormat, CartesianPlot::RangeFormat);
 			READ_INT_VALUE("yRangeFormat", yRangeFormat, CartesianPlot::RangeFormat);
 
 			READ_DOUBLE_VALUE("horizontalPadding", horizontalPadding);
 			READ_DOUBLE_VALUE("verticalPadding", verticalPadding);
 		} else if (!preview && reader->name() == "xRangeBreaks") {
 			//delete default rang break
 			d->xRangeBreaks.list.clear();
 
 			attribs = reader->attributes();
 			READ_INT_VALUE("enabled", xRangeBreakingEnabled, bool);
 		} else if (!preview && reader->name() == "xRangeBreak") {
 			attribs = reader->attributes();
 
 			RangeBreak b;
 			str = attribs.value("start").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("start").toString());
 			else
 				b.start = str.toDouble();
 
 			str = attribs.value("end").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("end").toString());
 			else
 				b.end = str.toDouble();
 
 			str = attribs.value("position").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("position").toString());
 			else
 				b.position = str.toDouble();
 
 			str = attribs.value("style").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("style").toString());
 			else
 				b.style = CartesianPlot::RangeBreakStyle(str.toInt());
 
 			d->xRangeBreaks.list << b;
 		} else if (!preview && reader->name() == "yRangeBreaks") {
 			//delete default rang break
 			d->yRangeBreaks.list.clear();
 
 			attribs = reader->attributes();
 			READ_INT_VALUE("enabled", yRangeBreakingEnabled, bool);
 		} else if (!preview && reader->name() == "yRangeBreak") {
 			attribs = reader->attributes();
 
 			RangeBreak b;
 			str = attribs.value("start").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("start").toString());
 			else
 				b.start = str.toDouble();
 
 			str = attribs.value("end").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("end").toString());
 			else
 				b.end = str.toDouble();
 
 			str = attribs.value("position").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("position").toString());
 			else
 				b.position = str.toDouble();
 
 			str = attribs.value("style").toString();
 			if (str.isEmpty())
 				reader->raiseWarning(attributeWarning.subs("style").toString());
 			else
 				b.style = CartesianPlot::RangeBreakStyle(str.toInt());
 
 			d->yRangeBreaks.list << b;
 		} else if (reader->name() == "textLabel") {
 			if (!titleLabelRead) {
 				//the first text label is always the title label
 				m_title->load(reader, preview);
 				titleLabelRead = true;
 
 				//TODO: the name is read in m_title->load() but we overwrite it here
 				//since the old projects don't have this " - Title" appendix yet that we add in init().
 				//can be removed in couple of releases
 				m_title->setName(name() + QLatin1String(" - ") + i18n("Title"));
 			} else {
 				TextLabel* label = new TextLabel("text label");
 				if (label->load(reader, preview)) {
 					addChildFast(label);
 					label->setParentGraphicsItem(graphicsItem());
 				} else {
 					delete label;
 					return false;
 				}
 			}
 		} else if (reader->name() == "plotArea")
 			m_plotArea->load(reader, preview);
 		else if (reader->name() == "axis") {
 			Axis* axis = new Axis("");
 			if (axis->load(reader, preview))
 				addChildFast(axis);
 			else {
 				delete axis;
 				return false;
 			}
 		} else if (reader->name() == "xyCurve") {
 			XYCurve* curve = new XYCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyEquationCurve") {
 			XYEquationCurve* curve = new XYEquationCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyDataReductionCurve") {
 			XYDataReductionCurve* curve = new XYDataReductionCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyDifferentiationCurve") {
 			XYDifferentiationCurve* curve = new XYDifferentiationCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyIntegrationCurve") {
 			XYIntegrationCurve* curve = new XYIntegrationCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyInterpolationCurve") {
 			XYInterpolationCurve* curve = new XYInterpolationCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xySmoothCurve") {
 			XYSmoothCurve* curve = new XYSmoothCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyFitCurve") {
 			XYFitCurve* curve = new XYFitCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyFourierFilterCurve") {
 			XYFourierFilterCurve* curve = new XYFourierFilterCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyFourierTransformCurve") {
 			XYFourierTransformCurve* curve = new XYFourierTransformCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyConvolutionCurve") {
 			XYConvolutionCurve* curve = new XYConvolutionCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "xyCorrelationCurve") {
 			XYCorrelationCurve* curve = new XYCorrelationCurve("");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else if (reader->name() == "cartesianPlotLegend") {
 			m_legend = new CartesianPlotLegend(this, "");
 			if (m_legend->load(reader, preview))
 				addChildFast(m_legend);
 			else {
 				delete m_legend;
 				return false;
 			}
 		} else if (reader->name() == "customPoint") {
 			CustomPoint* point = new CustomPoint(this, "");
 			if (point->load(reader, preview))
 				addChildFast(point);
 			else {
 				delete point;
 				return false;
 			}
 		} else if (reader->name() == "Histogram") {
 			Histogram* curve = new Histogram("Histogram");
 			if (curve->load(reader, preview))
 				addChildFast(curve);
 			else {
 				removeChild(curve);
 				return false;
 			}
 		} else { // unknown element
 			reader->raiseWarning(i18n("unknown cartesianPlot element '%1'", reader->name().toString()));
 			if (!reader->skipToEndElement()) return false;
 		}
 	}
 
 	if (preview)
 		return true;
 
 	d->retransform();
 
 	//if a theme was used, initialize the color palette
 	if (!d->theme.isEmpty()) {
 		//TODO: check whether the theme config really exists
 		KConfig config( ThemeHandler::themeFilePath(d->theme), KConfig::SimpleConfig );
 		this->setColorPalette(config);
 	} else {
 		//initialize the color palette with default colors
 		this->setColorPalette(KConfig());
 	}
 
 	return true;
 }
 
 //##############################################################################
 //#########################  Theme management ##################################
 //##############################################################################
 void CartesianPlot::loadTheme(const QString& theme) {
 	KConfig config(ThemeHandler::themeFilePath(theme), KConfig::SimpleConfig);
 	loadThemeConfig(config);
 }
 
 void CartesianPlot::loadThemeConfig(const KConfig& config) {
 	QString str = config.name();
 
 	// theme path is saved with UNIX dir separator
 	str = str.right(str.length() - str.lastIndexOf(QLatin1Char('/')) - 1);
 	DEBUG("	set theme to " << str.toStdString());
 	this->setTheme(str);
 
 	//load the color palettes for the curves
 	this->setColorPalette(config);
 
 	//load the theme for all the children
 	for (auto* child : children<WorksheetElement>(AbstractAspect::IncludeHidden))
 		child->loadThemeConfig(config);
 
 	Q_D(CartesianPlot);
 	d->update(this->rect());
 }
 
 void CartesianPlot::saveTheme(KConfig &config) {
 	const QVector<Axis*>& axisElements = children<Axis>(AbstractAspect::IncludeHidden);
 	const QVector<PlotArea*>& plotAreaElements = children<PlotArea>(AbstractAspect::IncludeHidden);
 	const QVector<TextLabel*>& textLabelElements = children<TextLabel>(AbstractAspect::IncludeHidden);
 
 	axisElements.at(0)->saveThemeConfig(config);
 	plotAreaElements.at(0)->saveThemeConfig(config);
 	textLabelElements.at(0)->saveThemeConfig(config);
 
 	for (auto *child : children<XYCurve>(AbstractAspect::IncludeHidden))
 		child->saveThemeConfig(config);
 }
 
 //Generating colors from 5-color theme palette
 void CartesianPlot::setColorPalette(const KConfig& config) {
 	if (config.hasGroup(QLatin1String("Theme"))) {
 		KConfigGroup group = config.group(QLatin1String("Theme"));
 
 		//read the five colors defining the palette
 		m_themeColorPalette.clear();
 		m_themeColorPalette.append(group.readEntry("ThemePaletteColor1", QColor()));
 		m_themeColorPalette.append(group.readEntry("ThemePaletteColor2", QColor()));
 		m_themeColorPalette.append(group.readEntry("ThemePaletteColor3", QColor()));
 		m_themeColorPalette.append(group.readEntry("ThemePaletteColor4", QColor()));
 		m_themeColorPalette.append(group.readEntry("ThemePaletteColor5", QColor()));
 	} else {
 		//no theme is available, provide 5 "default colors"
 		m_themeColorPalette.clear();
 		m_themeColorPalette.append(QColor(25, 25, 25));
 		m_themeColorPalette.append(QColor(0, 0, 127));
 		m_themeColorPalette.append(QColor(127 ,0, 0));
 		m_themeColorPalette.append(QColor(0, 127, 0));
 		m_themeColorPalette.append(QColor(85, 0, 127));
 	}
 
 	//generate 30 additional shades if the color palette contains more than one color
 	if (m_themeColorPalette.at(0) != m_themeColorPalette.at(1)) {
 		QColor c;
 
 		//3 factors to create shades from theme's palette
 		float fac[3] = {0.25f,0.45f,0.65f};
 
 		//Generate 15 lighter shades
 		for (int i = 0; i < 5; i++) {
 			for (int j = 1; j < 4; j++) {
 				c.setRed( m_themeColorPalette.at(i).red()*(1-fac[j-1]) );
 				c.setGreen( m_themeColorPalette.at(i).green()*(1-fac[j-1]) );
 				c.setBlue( m_themeColorPalette.at(i).blue()*(1-fac[j-1]) );
 				m_themeColorPalette.append(c);
 			}
 		}
 
 		//Generate 15 darker shades
 		for (int i = 0; i < 5; i++) {
 			for (int j = 4; j < 7; j++) {
 				c.setRed( m_themeColorPalette.at(i).red()+((255-m_themeColorPalette.at(i).red())*fac[j-4]) );
 				c.setGreen( m_themeColorPalette.at(i).green()+((255-m_themeColorPalette.at(i).green())*fac[j-4]) );
 				c.setBlue( m_themeColorPalette.at(i).blue()+((255-m_themeColorPalette.at(i).blue())*fac[j-4]) );
 				m_themeColorPalette.append(c);
 			}
 		}
 	}
 }
 
 const QList<QColor>& CartesianPlot::themeColorPalette() const {
 	return m_themeColorPalette;
 }
diff --git a/src/commonfrontend/worksheet/WorksheetView.cpp b/src/commonfrontend/worksheet/WorksheetView.cpp
index 4b500869a..a15ae0496 100644
--- a/src/commonfrontend/worksheet/WorksheetView.cpp
+++ b/src/commonfrontend/worksheet/WorksheetView.cpp
@@ -1,1916 +1,1919 @@
 /***************************************************************************
     File                 : WorksheetView.cpp
     Project              : LabPlot
     Description          : Worksheet view
     --------------------------------------------------------------------
     Copyright            : (C) 2009-2017 Alexander Semke (alexander.semke@web.de)
     Copyright            : (C) 2016-2018 Stefan-Gerlach (stefan.gerlach@uni.kn)
 
  ***************************************************************************/
 
 /***************************************************************************
  *                                                                         *
  *  This program is free software; you can redistribute it and/or modify   *
  *  it under the terms of the GNU General Public License as published by   *
  *  the Free Software Foundation; either version 2 of the License, or      *
  *  (at your option) any later version.                                    *
  *                                                                         *
  *  This program is distributed in the hope that it will be useful,        *
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of         *
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the          *
  *  GNU General Public License for more details.                           *
  *                                                                         *
  *   You should have received a copy of the GNU General Public License     *
  *   along with this program; if not, write to the Free Software           *
  *   Foundation, Inc., 51 Franklin Street, Fifth Floor,                    *
  *   Boston, MA  02110-1301  USA                                           *
  *                                                                         *
  ***************************************************************************/
 #include "commonfrontend/worksheet/WorksheetView.h"
 #include "backend/core/AbstractColumn.h"
 #include "backend/worksheet/plots/cartesian/Axis.h"
 #include "backend/worksheet/plots/cartesian/XYCurve.h"
 #include "backend/worksheet/plots/cartesian/XYCurvePrivate.h"
 #include "backend/worksheet/TextLabel.h"
 #include "commonfrontend/core/PartMdiView.h"
 #include "kdefrontend/widgets/ThemesWidget.h"
 #include "kdefrontend/worksheet/GridDialog.h"
 #include "kdefrontend/worksheet/PresenterWidget.h"
 #include "kdefrontend/worksheet/DynamicPresenterWidget.h"
 #include "backend/lib/trace.h"
 
 #include <QApplication>
 #include <QMdiArea>
 #include <QMenu>
 #include <QToolBar>
 #include <QDesktopWidget>
 #include <QWheelEvent>
 #include <QPrinter>
 #include <QSvgGenerator>
 #include <QImage>
 #include <QToolButton>
 #include <QGraphicsOpacityEffect>
 #include <QTimeLine>
 #include <QClipboard>
 #include <QMimeData>
 #include <QWidgetAction>
 
 #include <KColorScheme>
 #include <KLocalizedString>
 #include <KMessageBox>
 #include <KConfigGroup>
 
 #include <limits>
 
 /**
  * \class WorksheetView
  * \brief Worksheet view
  */
 
 /*!
   Constructur of the class.
   Creates a view for the Worksheet \c worksheet and initializes the internal model.
 */
 WorksheetView::WorksheetView(Worksheet* worksheet) : QGraphicsView(), m_worksheet(worksheet) {
 	setScene(m_worksheet->scene());
 
 	setRenderHint(QPainter::Antialiasing);
 	setRubberBandSelectionMode(Qt::ContainsItemBoundingRect);
 	setTransformationAnchor(QGraphicsView::AnchorViewCenter);
 	setResizeAnchor(QGraphicsView::AnchorViewCenter);
 	setMinimumSize(16, 16);
 	setFocusPolicy(Qt::StrongFocus);
 
 	if (m_worksheet->useViewSize()) {
 		setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
 		setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
 	}
 
 	viewport()->setAttribute( Qt::WA_OpaquePaintEvent );
 	viewport()->setAttribute( Qt::WA_NoSystemBackground );
 	setAcceptDrops(true);
 	setCacheMode(QGraphicsView::CacheBackground);
 
 	m_gridSettings.style = WorksheetView::NoGrid;
 
 	//signal/slot connections
 	connect(m_worksheet, SIGNAL(requestProjectContextMenu(QMenu*)), this, SLOT(createContextMenu(QMenu*)));
 	connect(m_worksheet, SIGNAL(itemSelected(QGraphicsItem*)), this, SLOT(selectItem(QGraphicsItem*)) );
 	connect(m_worksheet, SIGNAL(itemDeselected(QGraphicsItem*)), this, SLOT(deselectItem(QGraphicsItem*)) );
 	connect(m_worksheet, SIGNAL(requestUpdate()), this, SLOT(updateBackground()) );
 	connect(m_worksheet, SIGNAL(aspectAboutToBeRemoved(const AbstractAspect*)), this, SLOT(aspectAboutToBeRemoved(const AbstractAspect*)));
 	connect(m_worksheet, SIGNAL(useViewSizeRequested()), this, SLOT(useViewSizeRequested()) );
 	connect(m_worksheet, SIGNAL(layoutChanged(Worksheet::Layout)), this, SLOT(layoutChanged(Worksheet::Layout)) );
 	connect(scene(), SIGNAL(selectionChanged()), this, SLOT(selectionChanged()) );
 
 	//resize the view to make the complete scene visible.
 	//no need to resize the view when the project is being opened,
 	//all views will be resized to the stored values at the end
 	if (!m_worksheet->isLoading()) {
 		float w = Worksheet::convertFromSceneUnits(sceneRect().width(), Worksheet::Inch);
 		float h = Worksheet::convertFromSceneUnits(sceneRect().height(), Worksheet::Inch);
 		w *= QApplication::desktop()->physicalDpiX();
 		h *= QApplication::desktop()->physicalDpiY();
 		resize(w*1.1, h*1.1);
 	}
 
 	//rescale to the original size
 	static const float hscale = QApplication::desktop()->physicalDpiX()/(Worksheet::convertToSceneUnits(1,Worksheet::Inch));
 	static const float vscale = QApplication::desktop()->physicalDpiY()/(Worksheet::convertToSceneUnits(1,Worksheet::Inch));
 	setTransform(QTransform::fromScale(hscale, vscale));
 }
 
 void WorksheetView::initActions() {
 	auto* addNewActionGroup = new QActionGroup(this);
 	auto* zoomActionGroup = new QActionGroup(this);
 	auto* mouseModeActionGroup = new QActionGroup(this);
 	auto* layoutActionGroup = new QActionGroup(this);
 	auto* gridActionGroup = new QActionGroup(this);
 	gridActionGroup->setExclusive(true);
 	auto* magnificationActionGroup = new QActionGroup(this);
 
 	selectAllAction = new QAction(QIcon::fromTheme("edit-select-all"), i18n("Select All"), this);
 	selectAllAction->setShortcut(Qt::CTRL+Qt::Key_A);
 	this->addAction(selectAllAction);
 	connect(selectAllAction, SIGNAL(triggered()), SLOT(selectAllElements()));
 
 	deleteAction = new QAction(QIcon::fromTheme("edit-delete"), i18n("Delete"), this);
 	deleteAction->setShortcut(Qt::Key_Delete);
 	this->addAction(deleteAction);
 	connect(deleteAction, SIGNAL(triggered()), SLOT(deleteElement()));
 
 	backspaceAction = new QAction(this);
 	backspaceAction->setShortcut(Qt::Key_Backspace);
 	this->addAction(backspaceAction);
 	connect(backspaceAction, SIGNAL(triggered()), SLOT(deleteElement()));
 
 	//Zoom actions
 	zoomInViewAction = new QAction(QIcon::fromTheme("zoom-in"), i18n("Zoom In"), zoomActionGroup);
 	zoomInViewAction->setShortcut(Qt::CTRL+Qt::Key_Plus);
 
 	zoomOutViewAction = new QAction(QIcon::fromTheme("zoom-out"), i18n("Zoom Out"), zoomActionGroup);
 	zoomOutViewAction->setShortcut(Qt::CTRL+Qt::Key_Minus);
 
 	zoomOriginAction = new QAction(QIcon::fromTheme("zoom-original"), i18n("Original Size"), zoomActionGroup);
 	zoomOriginAction->setShortcut(Qt::CTRL+Qt::Key_1);
 
 	zoomFitPageHeightAction = new QAction(QIcon::fromTheme("zoom-fit-height"), i18n("Fit to Height"), zoomActionGroup);
 	zoomFitPageWidthAction = new QAction(QIcon::fromTheme("zoom-fit-width"), i18n("Fit to Width"), zoomActionGroup);
 	zoomFitSelectionAction = new QAction(i18n("Fit to Selection"), zoomActionGroup);
 
 	// Mouse mode actions
 	selectionModeAction = new QAction(QIcon::fromTheme("labplot-cursor-arrow"), i18n("Select and Edit"), mouseModeActionGroup);
 	selectionModeAction->setCheckable(true);
 
 	navigationModeAction = new QAction(QIcon::fromTheme("input-mouse"), i18n("Navigate"), mouseModeActionGroup);
 	navigationModeAction->setCheckable(true);
 
 	zoomSelectionModeAction = new QAction(QIcon::fromTheme("page-zoom"), i18n("Select and Zoom"), mouseModeActionGroup);
 	zoomSelectionModeAction->setCheckable(true);
 
 	//Magnification actions
 	noMagnificationAction = new QAction(QIcon::fromTheme("labplot-1x-zoom"), i18n("No Magnification"), magnificationActionGroup);
 	noMagnificationAction->setCheckable(true);
 	noMagnificationAction->setChecked(true);
 
 	twoTimesMagnificationAction = new QAction(QIcon::fromTheme("labplot-2x-zoom"), i18n("2x Magnification"), magnificationActionGroup);
 	twoTimesMagnificationAction->setCheckable(true);
 
 	threeTimesMagnificationAction = new QAction(QIcon::fromTheme("labplot-3x-zoom"), i18n("3x Magnification"), magnificationActionGroup);
 	threeTimesMagnificationAction->setCheckable(true);
 
 	fourTimesMagnificationAction = new QAction(QIcon::fromTheme("labplot-4x-zoom"), i18n("4x Magnification"), magnificationActionGroup);
 	fourTimesMagnificationAction->setCheckable(true);
 
 	fiveTimesMagnificationAction = new QAction(QIcon::fromTheme("labplot-5x-zoom"), i18n("5x Magnification"), magnificationActionGroup);
 	fiveTimesMagnificationAction->setCheckable(true);
 
 	//TODO implement later "group selection action" where multiple objects can be selected by drawing a rectangular
 // 	selectionModeAction = new QAction(QIcon::fromTheme("select-rectangular"), i18n("Selection"), mouseModeActionGroup);
 // 	selectionModeAction->setCheckable(true);
 
 	//"Add new" related actions
 	addCartesianPlot1Action = new QAction(QIcon::fromTheme("labplot-xy-plot-four-axes"), i18n("Box Plot, Four Axes"), addNewActionGroup);
 	addCartesianPlot2Action = new QAction(QIcon::fromTheme("labplot-xy-plot-two-axes"), i18n("Box Plot, Two Axes"), addNewActionGroup);
 	addCartesianPlot3Action = new QAction(QIcon::fromTheme("labplot-xy-plot-two-axes-centered"), i18n("Two Axes, Centered"), addNewActionGroup);
 	addCartesianPlot4Action = new QAction(QIcon::fromTheme("labplot-xy-plot-two-axes-centered-origin"), i18n("Two Axes, Crossing at Origin"), addNewActionGroup);
 	addTextLabelAction = new QAction(QIcon::fromTheme("draw-text"), i18n("Text Label"), addNewActionGroup);
 	addBarChartPlot = new QAction(QIcon::fromTheme("office-chart-line"), i18n("Bar Chart"), addNewActionGroup);
 	//Layout actions
 	verticalLayoutAction = new QAction(QIcon::fromTheme("labplot-editvlayout"), i18n("Vertical Layout"), layoutActionGroup);
 	verticalLayoutAction->setCheckable(true);
 
 	horizontalLayoutAction = new QAction(QIcon::fromTheme("labplot-edithlayout"), i18n("Horizontal Layout"), layoutActionGroup);
 	horizontalLayoutAction->setCheckable(true);
 
 	gridLayoutAction = new QAction(QIcon::fromTheme("labplot-editgrid"), i18n("Grid Layout"), layoutActionGroup);
 	gridLayoutAction->setCheckable(true);
 
 	breakLayoutAction = new QAction(QIcon::fromTheme("labplot-editbreaklayout"), i18n("Break Layout"), layoutActionGroup);
 	breakLayoutAction->setEnabled(false);
 
 	//Grid actions
 	noGridAction = new QAction(i18n("No Grid"), gridActionGroup);
 	noGridAction->setCheckable(true);
 	noGridAction->setChecked(true);
 	noGridAction->setData(WorksheetView::NoGrid);
 
 	denseLineGridAction = new QAction(i18n("Dense Line Grid"), gridActionGroup);
 	denseLineGridAction->setCheckable(true);
 
 	sparseLineGridAction = new QAction(i18n("Sparse Line Grid"), gridActionGroup);
 	sparseLineGridAction->setCheckable(true);
 
 	denseDotGridAction = new QAction(i18n("Dense Dot Grid"), gridActionGroup);
 	denseDotGridAction->setCheckable(true);
 
 	sparseDotGridAction = new QAction(i18n("Sparse Dot Grid"), gridActionGroup);
 	sparseDotGridAction->setCheckable(true);
 
 	customGridAction = new QAction(i18n("Custom Grid"), gridActionGroup);
 	customGridAction->setCheckable(true);
 
 	snapToGridAction = new QAction(i18n("Snap to Grid"), this);
 	snapToGridAction->setCheckable(true);
 
 	showPresenterMode = new QAction(QIcon::fromTheme("view-fullscreen"), i18n("Show in Presenter Mode"), this);
 
 	//check the action corresponding to the currently active layout in worksheet
 	this->layoutChanged(m_worksheet->layout());
 
 	connect(addNewActionGroup, SIGNAL(triggered(QAction*)), this, SLOT(addNew(QAction*)));
 	connect(mouseModeActionGroup, SIGNAL(triggered(QAction*)), this, SLOT(mouseModeChanged(QAction*)));
 	connect(zoomActionGroup, SIGNAL(triggered(QAction*)), this, SLOT(changeZoom(QAction*)));
 	connect(magnificationActionGroup, SIGNAL(triggered(QAction*)), this, SLOT(magnificationChanged(QAction*)));
 	connect(layoutActionGroup, SIGNAL(triggered(QAction*)), this, SLOT(changeLayout(QAction*)));
 	connect(gridActionGroup, SIGNAL(triggered(QAction*)), this, SLOT(changeGrid(QAction*)));
 	connect(snapToGridAction, SIGNAL(triggered()), this, SLOT(changeSnapToGrid()));
 	connect(showPresenterMode, SIGNAL(triggered()), this, SLOT(presenterMode()));
 
 	//worksheet control actions
 	plotsLockedAction = new QAction(i18n("Non-interactive Plots"), this);
 	plotsLockedAction->setToolTip(i18n("If activated, plots on the worksheet don't react on drag and mouse wheel events."));
 	plotsLockedAction->setCheckable(true);
 	plotsLockedAction->setChecked(m_worksheet->plotsLocked());
 	connect(plotsLockedAction, &QAction::triggered, this, &WorksheetView::plotsLockedActionChanged);
 
 	//action for cartesian plots
 	auto* cartesianPlotActionModeActionGroup = new QActionGroup(this);
 	cartesianPlotActionModeActionGroup->setExclusive(true);
 	cartesianPlotApplyToSelectionAction = new QAction(i18n("Selected Plots"), cartesianPlotActionModeActionGroup);
 	cartesianPlotApplyToSelectionAction->setCheckable(true);
 	cartesianPlotApplyToAllAction = new QAction(i18n("All Plots"), cartesianPlotActionModeActionGroup);
 	cartesianPlotApplyToAllAction->setCheckable(true);
 	setCartesianPlotActionMode(m_worksheet->cartesianPlotActionMode());
 	connect(cartesianPlotActionModeActionGroup, SIGNAL(triggered(QAction*)), SLOT(cartesianPlotActionModeChanged(QAction*)));
 
 	auto* cartesianPlotMouseModeActionGroup = new QActionGroup(this);
 	cartesianPlotMouseModeActionGroup->setExclusive(true);
 	cartesianPlotSelectionModeAction = new QAction(QIcon::fromTheme("labplot-cursor-arrow"), i18n("Select and Edit"), cartesianPlotMouseModeActionGroup);
 	cartesianPlotSelectionModeAction->setCheckable(true);
 	cartesianPlotSelectionModeAction->setChecked(true);
 
 	cartesianPlotZoomSelectionModeAction = new QAction(QIcon::fromTheme("labplot-zoom-select"), i18n("Select Region and Zoom In"), cartesianPlotMouseModeActionGroup);
 	cartesianPlotZoomSelectionModeAction->setCheckable(true);
 
 	cartesianPlotZoomXSelectionModeAction = new QAction(QIcon::fromTheme("labplot-zoom-select-x"), i18n("Select x-region and Zoom In"), cartesianPlotMouseModeActionGroup);
 	cartesianPlotZoomXSelectionModeAction->setCheckable(true);
 
 	cartesianPlotZoomYSelectionModeAction = new QAction(QIcon::fromTheme("labplot-zoom-select-y"), i18n("Select y-region and Zoom In"), cartesianPlotMouseModeActionGroup);
 	cartesianPlotZoomYSelectionModeAction->setCheckable(true);
 
 	connect(cartesianPlotMouseModeActionGroup, SIGNAL(triggered(QAction*)), SLOT(cartesianPlotMouseModeChanged(QAction*)));
 
 	auto* cartesianPlotAddNewActionGroup = new QActionGroup(this);
 	addCurveAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("xy-curve"), cartesianPlotAddNewActionGroup);
 	addHistogramAction = new QAction(QIcon::fromTheme("view-object-histogram-linear"), i18n("Histogram"), cartesianPlotAddNewActionGroup);
 	addEquationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-equation-curve"), i18n("xy-curve from a mathematical Equation"), cartesianPlotAddNewActionGroup);
 	// TODO: no own icons yet
 	addDataOperationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("xy-curve from a Data Operation"), cartesianPlotAddNewActionGroup);
 //	addDataOperationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-data-operation-curve"), i18n("xy-curve From a Data Operation"), cartesianPlotAddNewActionGroup);
 	addDataReductionCurveAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("xy-curve from a Data Reduction"), cartesianPlotAddNewActionGroup);
 //	addDataReductionCurveAction = new QAction(QIcon::fromTheme("labplot-xy-data-reduction-curve"), i18n("xy-curve From a Data Reduction"), cartesianPlotAddNewActionGroup);
 	addDifferentiationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("xy-curve from a Differentiation"), cartesianPlotAddNewActionGroup);
 //	addDifferentiationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-differentiation-curve"), i18n("xy-curve From a Differentiation"), cartesianPlotAddNewActionGroup);
 	addIntegrationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("xy-curvefFrom an Integration"), cartesianPlotAddNewActionGroup);
 //	addIntegrationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-integration-curve"), i18n("xy-curve From an Integration"), cartesianPlotAddNewActionGroup);
 	addConvolutionCurveAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("xy-curve from a (De-)Convolution"), cartesianPlotAddNewActionGroup);
 //	addConvolutionCurveAction = new QAction(QIcon::fromTheme("labplot-xy-convolution-curve"), i18n("xy-curve From a (De-)Convolution"), cartesianPlotAddNewActionGroup);
 	addCorrelationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("xy-curve from a Correlation"), cartesianPlotAddNewActionGroup);
 //	addCorrelationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-convolution-curve"), i18n("xy-curve From a Correlation"), cartesianPlotAddNewActionGroup);
 
 	addInterpolationCurveAction = new QAction(QIcon::fromTheme("labplot-xy-interpolation-curve"), i18n("xy-curve From an Interpolation"), cartesianPlotAddNewActionGroup);
 	addSmoothCurveAction = new QAction(QIcon::fromTheme("labplot-xy-smoothing-curve"), i18n("xy-curve from a Smooth"), cartesianPlotAddNewActionGroup);
 	addFitCurveAction = new QAction(QIcon::fromTheme("labplot-xy-fit-curve"), i18n("xy-curve from a Fit to Data"), cartesianPlotAddNewActionGroup);
 	addFourierFilterCurveAction = new QAction(QIcon::fromTheme("labplot-xy-fourier-filter-curve"), i18n("xy-curve from a Fourier Filter"), cartesianPlotAddNewActionGroup);
 	addFourierTransformCurveAction = new QAction(QIcon::fromTheme("labplot-xy-fourier-transform-curve"), i18n("xy-curve from a Fourier Transform"), cartesianPlotAddNewActionGroup);
 	addLegendAction = new QAction(QIcon::fromTheme("text-field"), i18n("Legend"), cartesianPlotAddNewActionGroup);
 	addHorizontalAxisAction = new QAction(QIcon::fromTheme("labplot-axis-horizontal"), i18n("Horizontal Axis"), cartesianPlotAddNewActionGroup);
 	addVerticalAxisAction = new QAction(QIcon::fromTheme("labplot-axis-vertical"), i18n("Vertical Axis"), cartesianPlotAddNewActionGroup);
 	addCustomPointAction = new QAction(QIcon::fromTheme("draw-cross"), i18n("Custom Point"), cartesianPlotAddNewActionGroup);
 
 	// Analysis menu
 	// TODO: no own icons yet
 	addDataOperationAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("Data Operation"), cartesianPlotAddNewActionGroup);
 //	addDataOperationAction = new QAction(QIcon::fromTheme("labplot-xy-data-operation-curve"), i18n("Data Operation"), cartesianPlotAddNewActionGroup);
 	addDataReductionAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("Data Reduction"), cartesianPlotAddNewActionGroup);
 //	addDataReductionAction = new QAction(QIcon::fromTheme("labplot-xy-data-reduction-curve"), i18n("Data Reduction"), cartesianPlotAddNewActionGroup);
 	addDifferentiationAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("Differentiation"), cartesianPlotAddNewActionGroup);
 //	addDifferentiationAction = new QAction(QIcon::fromTheme("labplot-xy-differentiation-curve"), i18n("Differentiation"), cartesianPlotAddNewActionGroup);
 	addIntegrationAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("Integration"), cartesianPlotAddNewActionGroup);
 //	addIntegrationAction = new QAction(QIcon::fromTheme("labplot-xy-integration-curve"), i18n("Integration"), cartesianPlotAddNewActionGroup);
 	addConvolutionAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("Convolution/Deconvolution"), cartesianPlotAddNewActionGroup);
 //	addConvolutionAction = new QAction(QIcon::fromTheme("labplot-xy-convolution-curve"), i18n("Convolution/Deconvolution"), cartesianPlotAddNewActionGroup);
 	addCorrelationAction = new QAction(QIcon::fromTheme("labplot-xy-curve"), i18n("Correlation"), cartesianPlotAddNewActionGroup);
 //	addCorrelationAction = new QAction(QIcon::fromTheme("labplot-xy-convolution-curve"), i18n("Correlation"), cartesianPlotAddNewActionGroup);
 
 	addInterpolationAction = new QAction(QIcon::fromTheme("labplot-xy-interpolation-curve"), i18n("Interpolation"), cartesianPlotAddNewActionGroup);
 	addSmoothAction = new QAction(QIcon::fromTheme("labplot-xy-smoothing-curve"), i18n("Smooth"), cartesianPlotAddNewActionGroup);
 	addFitAction = new QAction(QIcon::fromTheme("labplot-xy-fit-curve"), i18n("Data Fitting"), cartesianPlotAddNewActionGroup);
 	addFourierFilterAction = new QAction(QIcon::fromTheme("labplot-xy-fourier-filter-curve"), i18n("Fourier Filter"), cartesianPlotAddNewActionGroup);
 	addFourierTransformAction = new QAction(QIcon::fromTheme("labplot-xy-fourier-transform-curve"), i18n("Fourier Transform"), cartesianPlotAddNewActionGroup);
 
 	connect(cartesianPlotAddNewActionGroup, SIGNAL(triggered(QAction*)), SLOT(cartesianPlotAddNew(QAction*)));
 
 	auto* cartesianPlotNavigationGroup = new QActionGroup(this);
 	scaleAutoAction = new QAction(QIcon::fromTheme("labplot-auto-scale-all"), i18n("Auto Scale"), cartesianPlotNavigationGroup);
 	scaleAutoAction->setData(CartesianPlot::ScaleAuto);
 	scaleAutoXAction = new QAction(QIcon::fromTheme("labplot-auto-scale-x"), i18n("Auto Scale X"), cartesianPlotNavigationGroup);
 	scaleAutoXAction->setData(CartesianPlot::ScaleAutoX);
 	scaleAutoYAction = new QAction(QIcon::fromTheme("labplot-auto-scale-y"), i18n("Auto Scale Y"), cartesianPlotNavigationGroup);
 	scaleAutoYAction->setData(CartesianPlot::ScaleAutoY);
 	zoomInAction = new QAction(QIcon::fromTheme("zoom-in"), i18n("Zoom In"), cartesianPlotNavigationGroup);
 	zoomInAction->setData(CartesianPlot::ZoomIn);
 	zoomOutAction = new QAction(QIcon::fromTheme("zoom-out"), i18n("Zoom Out"), cartesianPlotNavigationGroup);
 	zoomOutAction->setData(CartesianPlot::ZoomOut);
 	zoomInXAction = new QAction(QIcon::fromTheme("labplot-zoom-in-x"), i18n("Zoom In X"), cartesianPlotNavigationGroup);
 	zoomInXAction->setData(CartesianPlot::ZoomInX);
 	zoomOutXAction = new QAction(QIcon::fromTheme("labplot-zoom-out-x"), i18n("Zoom Out X"), cartesianPlotNavigationGroup);
 	zoomOutXAction->setData(CartesianPlot::ZoomOutX);
 	zoomInYAction = new QAction(QIcon::fromTheme("labplot-zoom-in-y"), i18n("Zoom In Y"), cartesianPlotNavigationGroup);
 	zoomInYAction->setData(CartesianPlot::ZoomInY);
 	zoomOutYAction = new QAction(QIcon::fromTheme("labplot-zoom-out-y"), i18n("Zoom Out Y"), cartesianPlotNavigationGroup);
 	zoomOutYAction->setData(CartesianPlot::ZoomOutY);
 	shiftLeftXAction = new QAction(QIcon::fromTheme("labplot-shift-left-x"), i18n("Shift Left X"), cartesianPlotNavigationGroup);
 	shiftLeftXAction->setData(CartesianPlot::ShiftLeftX);
 	shiftRightXAction = new QAction(QIcon::fromTheme("labplot-shift-right-x"), i18n("Shift Right X"), cartesianPlotNavigationGroup);
 	shiftRightXAction->setData(CartesianPlot::ShiftRightX);
 	shiftUpYAction = new QAction(QIcon::fromTheme("labplot-shift-up-y"), i18n("Shift Up Y"), cartesianPlotNavigationGroup);
 	shiftUpYAction->setData(CartesianPlot::ShiftUpY);
 	shiftDownYAction = new QAction(QIcon::fromTheme("labplot-shift-down-y"), i18n("Shift Down Y"), cartesianPlotNavigationGroup);
 	shiftDownYAction->setData(CartesianPlot::ShiftDownY);
 
 	connect(cartesianPlotNavigationGroup, SIGNAL(triggered(QAction*)), SLOT(cartesianPlotNavigationChanged(QAction*)));
 
 	//set some default values
 	selectionModeAction->setChecked(true);
 	handleCartesianPlotActions();
 	currentZoomAction = zoomInViewAction;
 	currentMagnificationAction = noMagnificationAction;
 }
 
 void WorksheetView::initMenus() {
 	initActions();
 
 	m_addNewCartesianPlotMenu = new QMenu(i18n("xy-plot"), this);
 	m_addNewCartesianPlotMenu->addAction(addCartesianPlot1Action);
 	m_addNewCartesianPlotMenu->addAction(addCartesianPlot2Action);
 	m_addNewCartesianPlotMenu->addAction(addCartesianPlot3Action);
 	m_addNewCartesianPlotMenu->addAction(addCartesianPlot4Action);
 
 	m_addNewMenu = new QMenu(i18n("Add New"), this);
 	m_addNewMenu->addMenu(m_addNewCartesianPlotMenu)->setIcon(QIcon::fromTheme("office-chart-line"));
 	m_addNewMenu->addSeparator();
 	m_addNewMenu->addAction(addTextLabelAction);
 
 	m_viewMouseModeMenu = new QMenu(i18n("Mouse Mode"), this);
 	m_viewMouseModeMenu->setIcon(QIcon::fromTheme("input-mouse"));
 	m_viewMouseModeMenu->addAction(selectionModeAction);
 	m_viewMouseModeMenu->addAction(navigationModeAction);
 	m_viewMouseModeMenu->addAction(zoomSelectionModeAction);
 
 	m_zoomMenu = new QMenu(i18n("Zoom"), this);
 	m_zoomMenu->setIcon(QIcon::fromTheme("zoom-draw"));
 	m_zoomMenu->addAction(zoomInViewAction);
 	m_zoomMenu->addAction(zoomOutViewAction);
 	m_zoomMenu->addAction(zoomOriginAction);
 	m_zoomMenu->addAction(zoomFitPageHeightAction);
 	m_zoomMenu->addAction(zoomFitPageWidthAction);
 	m_zoomMenu->addAction(zoomFitSelectionAction);
 
 	m_magnificationMenu = new QMenu(i18n("Magnification"), this);
 	m_magnificationMenu->setIcon(QIcon::fromTheme("labplot-zoom"));
 	m_magnificationMenu->addAction(noMagnificationAction);
 	m_magnificationMenu->addAction(twoTimesMagnificationAction);
 	m_magnificationMenu->addAction(threeTimesMagnificationAction);
 	m_magnificationMenu->addAction(fourTimesMagnificationAction);
 	m_magnificationMenu->addAction(fiveTimesMagnificationAction);
 
 	m_layoutMenu = new QMenu(i18n("Layout"), this);
 	m_layoutMenu->addAction(verticalLayoutAction);
 	m_layoutMenu->addAction(horizontalLayoutAction);
 	m_layoutMenu->addAction(gridLayoutAction);
 	m_layoutMenu->addSeparator();
 	m_layoutMenu->addAction(breakLayoutAction);
 
 	m_gridMenu = new QMenu(i18n("Grid"), this);
 	m_gridMenu->setIcon(QIcon::fromTheme("view-grid"));
 	m_gridMenu->addAction(noGridAction);
 	m_gridMenu->addSeparator();
 	m_gridMenu->addAction(sparseLineGridAction);
 	m_gridMenu->addAction(denseLineGridAction);
 	m_gridMenu->addSeparator();
 	m_gridMenu->addAction(sparseDotGridAction);
 	m_gridMenu->addAction(denseDotGridAction);
 	m_gridMenu->addSeparator();
 	m_gridMenu->addAction(customGridAction);
 	//TODO: implement "snap to grid" and activate this action
 // 	m_gridMenu->addSeparator();
 // 	m_gridMenu->addAction(snapToGridAction);
 
 	m_cartesianPlotMenu = new QMenu(i18n("Cartesian Plot"), this);
 
 	m_cartesianPlotMouseModeMenu = new QMenu(i18n("Mouse Mode"), this);
 	m_cartesianPlotMouseModeMenu->setIcon(QIcon::fromTheme("input-mouse"));
 	m_cartesianPlotMouseModeMenu->addAction(cartesianPlotSelectionModeAction);
 	m_cartesianPlotMouseModeMenu->addAction(cartesianPlotZoomSelectionModeAction);
 	m_cartesianPlotMouseModeMenu->addAction(cartesianPlotZoomXSelectionModeAction);
 	m_cartesianPlotMouseModeMenu->addAction(cartesianPlotZoomYSelectionModeAction);
 	m_cartesianPlotMouseModeMenu->addSeparator();
 
 	m_cartesianPlotAddNewMenu = new QMenu(i18n("Add New"), this);
 	m_cartesianPlotAddNewMenu->addAction(addCurveAction);
 	m_cartesianPlotAddNewMenu->addAction(addHistogramAction);
 	m_cartesianPlotAddNewMenu->addAction(addEquationCurveAction);
 	m_cartesianPlotAddNewMenu->addSeparator();
 // 	m_cartesianPlotAddNewMenu->addAction(addDataOperationCurveAction);
 	m_cartesianPlotAddNewMenu->addAction(addDataReductionCurveAction);
 	m_cartesianPlotAddNewMenu->addAction(addDifferentiationCurveAction);
 	m_cartesianPlotAddNewMenu->addAction(addIntegrationCurveAction);
 	m_cartesianPlotAddNewMenu->addAction(addInterpolationCurveAction);
 	m_cartesianPlotAddNewMenu->addAction(addSmoothCurveAction);
 	m_cartesianPlotAddNewMenu->addAction(addFitCurveAction);
 	m_cartesianPlotAddNewMenu->addAction(addFourierFilterCurveAction);
 	m_cartesianPlotAddNewMenu->addAction(addFourierTransformCurveAction);
 	m_cartesianPlotAddNewMenu->addAction(addConvolutionCurveAction);
 	m_cartesianPlotAddNewMenu->addAction(addCorrelationCurveAction);
 	m_cartesianPlotAddNewMenu->addSeparator();
 	m_cartesianPlotAddNewMenu->addAction(addLegendAction);
 	m_cartesianPlotAddNewMenu->addSeparator();
 	m_cartesianPlotAddNewMenu->addAction(addHorizontalAxisAction);
 	m_cartesianPlotAddNewMenu->addAction(addVerticalAxisAction);
 
 	m_cartesianPlotZoomMenu = new QMenu(i18n("Zoom/Navigate"), this);
 	m_cartesianPlotZoomMenu->setIcon(QIcon::fromTheme("zoom-draw"));
 	m_cartesianPlotZoomMenu->addAction(scaleAutoAction);
 	m_cartesianPlotZoomMenu->addAction(scaleAutoXAction);
 	m_cartesianPlotZoomMenu->addAction(scaleAutoYAction);
 	m_cartesianPlotZoomMenu->addSeparator();
 	m_cartesianPlotZoomMenu->addAction(zoomInAction);
 	m_cartesianPlotZoomMenu->addAction(zoomOutAction);
 	m_cartesianPlotZoomMenu->addSeparator();
 	m_cartesianPlotZoomMenu->addAction(zoomInXAction);
 	m_cartesianPlotZoomMenu->addAction(zoomOutXAction);
 	m_cartesianPlotZoomMenu->addSeparator();
 	m_cartesianPlotZoomMenu->addAction(zoomInYAction);
 	m_cartesianPlotZoomMenu->addAction(zoomOutYAction);
 	m_cartesianPlotZoomMenu->addSeparator();
 	m_cartesianPlotZoomMenu->addAction(shiftLeftXAction);
 	m_cartesianPlotZoomMenu->addAction(shiftRightXAction);
 	m_cartesianPlotZoomMenu->addSeparator();
 	m_cartesianPlotZoomMenu->addAction(shiftUpYAction);
 	m_cartesianPlotZoomMenu->addAction(shiftDownYAction);
 
 	m_cartesianPlotActionModeMenu = new QMenu(i18n("Apply Actions to"), this);
 	m_cartesianPlotActionModeMenu->addAction(cartesianPlotApplyToSelectionAction);
 	m_cartesianPlotActionModeMenu->addAction(cartesianPlotApplyToAllAction);
 
 	m_cartesianPlotMenu->addMenu(m_cartesianPlotMouseModeMenu);
 	m_cartesianPlotMenu->addMenu(m_cartesianPlotAddNewMenu);
 	m_cartesianPlotMenu->addMenu(m_cartesianPlotZoomMenu);
 	m_cartesianPlotMenu->addSeparator();
 	m_cartesianPlotMenu->addMenu(m_cartesianPlotActionModeMenu);
 	m_cartesianPlotMenu->addAction(plotsLockedAction);
 
 	// Data manipulation menu
 	m_dataManipulationMenu = new QMenu(i18n("Data Manipulation"));
 	m_dataManipulationMenu->setIcon(QIcon::fromTheme("zoom-draw"));
 	m_dataManipulationMenu->addAction(addDataOperationAction);
 	m_dataManipulationMenu->addAction(addDataReductionAction);
 
 	//themes menu
 	m_themeMenu = new QMenu(i18n("Apply Theme"));
 	auto* themeWidget = new ThemesWidget(nullptr);
 	connect(themeWidget, SIGNAL(themeSelected(QString)), m_worksheet, SLOT(setTheme(QString)));
 	connect(themeWidget, SIGNAL(themeSelected(QString)), m_themeMenu, SLOT(close()));
 
 	auto* widgetAction = new QWidgetAction(this);
 	widgetAction->setDefaultWidget(themeWidget);
 	m_themeMenu->addAction(widgetAction);
 
 	m_menusInitialized = true;
 }
 
 /*!
  * Populates the menu \c menu with the worksheet and worksheet view relevant actions.
  * The menu is used
  *   - as the context menu in WorksheetView
  *   - as the "worksheet menu" in the main menu-bar (called form MainWin)
  *   - as a part of the worksheet context menu in project explorer
  */
 void WorksheetView::createContextMenu(QMenu* menu) {
 	Q_ASSERT(menu != nullptr);
 
 	if (!m_menusInitialized)
 		initMenus();
 
 	QAction* firstAction = nullptr;
 	// if we're populating the context menu for the project explorer, then
 	//there're already actions available there. Skip the first title-action
 	//and insert the action at the beginning of the menu.
 	if (menu->actions().size() > 1)
 		firstAction = menu->actions().at(1);
 
 	menu->insertMenu(firstAction, m_addNewMenu);
 	menu->insertSeparator(firstAction);
 	menu->insertMenu(firstAction, m_viewMouseModeMenu);
 	menu->insertMenu(firstAction, m_zoomMenu);
 	menu->insertMenu(firstAction, m_magnificationMenu);
 	menu->insertMenu(firstAction, m_layoutMenu);
 	menu->insertMenu(firstAction, m_gridMenu);
 	menu->insertMenu(firstAction, m_themeMenu);
 	menu->insertSeparator(firstAction);
 	menu->insertAction(firstAction, plotsLockedAction);
 	menu->insertSeparator(firstAction);
 	menu->insertMenu(firstAction, m_cartesianPlotMenu);
 	menu->insertSeparator(firstAction);
 	menu->insertAction(firstAction, showPresenterMode);
 	menu->insertSeparator(firstAction);
 }
 
 void WorksheetView::createAnalysisMenu(QMenu* menu) {
 	Q_ASSERT(menu != nullptr);
 
 	if (!m_menusInitialized)
 		initMenus();
 
 	// Data manipulation menu
 	menu->insertMenu(nullptr, m_dataManipulationMenu);
 
 	menu->addAction(addDifferentiationAction);
 	menu->addAction(addIntegrationAction);
 	menu->addAction(addInterpolationAction);
 	menu->addAction(addSmoothAction);
 	menu->addAction(addFitAction);
 	menu->addAction(addFourierFilterAction);
 	menu->addAction(addFourierTransformAction);
 	menu->addAction(addConvolutionAction);
 	menu->addAction(addCorrelationAction);
 }
 
 void WorksheetView::fillToolBar(QToolBar* toolBar) {
 	toolBar->addSeparator();
 	tbNewCartesianPlot = new QToolButton(toolBar);
 	tbNewCartesianPlot->setPopupMode(QToolButton::MenuButtonPopup);
 	tbNewCartesianPlot->setMenu(m_addNewCartesianPlotMenu);
 	tbNewCartesianPlot->setDefaultAction(addCartesianPlot1Action);
 	toolBar->addWidget(tbNewCartesianPlot);
 	toolBar->addAction(addTextLabelAction);
 
 	toolBar->addSeparator();
 	toolBar->addAction(verticalLayoutAction);
 	toolBar->addAction(horizontalLayoutAction);
 	toolBar->addAction(gridLayoutAction);
 	toolBar->addAction(breakLayoutAction);
 
 	toolBar->addSeparator();
 	toolBar->addAction(selectionModeAction);
 	toolBar->addAction(navigationModeAction);
 	toolBar->addAction(zoomSelectionModeAction);
 	tbZoom = new QToolButton(toolBar);
 	tbZoom->setPopupMode(QToolButton::MenuButtonPopup);
 	tbZoom->setMenu(m_zoomMenu);
 	tbZoom->setDefaultAction(currentZoomAction);
 	toolBar->addWidget(tbZoom);
 
 	tbMagnification = new QToolButton(toolBar);
 	tbMagnification->setPopupMode(QToolButton::MenuButtonPopup);
 	tbMagnification->setMenu(m_magnificationMenu);
 	tbMagnification->setDefaultAction(currentMagnificationAction);
 	toolBar->addWidget(tbMagnification);
 }
 
 void WorksheetView::fillCartesianPlotToolBar(QToolBar* toolBar) {
 	toolBar->addAction(cartesianPlotSelectionModeAction);
 	toolBar->addAction(cartesianPlotZoomSelectionModeAction);
 	toolBar->addAction(cartesianPlotZoomXSelectionModeAction);
 	toolBar->addAction(cartesianPlotZoomYSelectionModeAction);
 	toolBar->addSeparator();
 	toolBar->addAction(addCurveAction);
+	toolBar->addAction(addHistogramAction);
 	toolBar->addAction(addEquationCurveAction);
 // don't over-populate the tool bar
 //	toolBar->addAction(addDifferentiationCurveAction);
 //	toolBar->addAction(addIntegrationCurveAction);
 //	toolBar->addAction(addDataOperationCurveAction);
 //	toolBar->addAction(addDataReductionCurveAction);
 //	toolBar->addAction(addInterpolationCurveAction);
 //	toolBar->addAction(addSmoothCurveAction);
 //	toolBar->addAction(addFitCurveAction);
 //	toolBar->addAction(addFourierFilterCurveAction);
 //	toolBar->addAction(addFourierTransformCurveAction);
 //	toolBar->addAction(addConvolutionCurveAction);
 //	toolBar->addAction(addCorrelationCurveAction);
+	toolBar->addSeparator();
 	toolBar->addAction(addLegendAction);
 	toolBar->addSeparator();
 	toolBar->addAction(addHorizontalAxisAction);
 	toolBar->addAction(addVerticalAxisAction);
 	toolBar->addSeparator();
 	toolBar->addAction(scaleAutoAction);
 	toolBar->addAction(scaleAutoXAction);
 	toolBar->addAction(scaleAutoYAction);
 	toolBar->addAction(zoomInAction);
 	toolBar->addAction(zoomOutAction);
 	toolBar->addAction(zoomInXAction);
 	toolBar->addAction(zoomOutXAction);
 	toolBar->addAction(zoomInYAction);
 	toolBar->addAction(zoomOutYAction);
 	toolBar->addAction(shiftLeftXAction);
 	toolBar->addAction(shiftRightXAction);
 	toolBar->addAction(shiftUpYAction);
 	toolBar->addAction(shiftDownYAction);
 
 	handleCartesianPlotActions();
 }
 
 void WorksheetView::setScene(QGraphicsScene* scene) {
 	QGraphicsView::setScene(scene);
 }
 
 void WorksheetView::setIsClosing() {
 	m_isClosing = true;
 }
 
 void WorksheetView::setCartesianPlotActionMode(Worksheet::CartesianPlotActionMode mode) {
 	if (mode == Worksheet::CartesianPlotActionMode::ApplyActionToAll)
 		cartesianPlotApplyToAllAction->setChecked(true);
 	else
 		cartesianPlotApplyToSelectionAction->setChecked(true);
 }
 
 void WorksheetView::setPlotLock(bool lock) {
 	plotsLockedAction->setChecked(lock);
 }
 
 void WorksheetView::drawForeground(QPainter* painter, const QRectF& rect) {
 	if (m_mouseMode == ZoomSelectionMode && m_selectionBandIsShown) {
 		painter->save();
 		const QRectF& selRect = mapToScene(QRect(m_selectionStart, m_selectionEnd).normalized()).boundingRect();
 		//TODO: don't hardcode for black here, use a a different color depending on the theme of the worksheet/plot under the mouse cursor?
 		painter->setPen(QPen(Qt::black, 5/transform().m11()));
 		painter->drawRect(selRect);
 		painter->setBrush(QApplication::palette().color(QPalette::Highlight));
 		painter->setOpacity(0.2);
 		painter->drawRect(selRect);
 		painter->restore();
 	}
 	QGraphicsView::drawForeground(painter, rect);
 }
 
 void WorksheetView::drawBackgroundItems(QPainter* painter, const QRectF& scene_rect) {
 	// canvas
 	painter->setOpacity(m_worksheet->backgroundOpacity());
 	if (m_worksheet->backgroundType() == PlotArea::Color) {
 		switch (m_worksheet->backgroundColorStyle()) {
 		case PlotArea::SingleColor: {
 				painter->setBrush(QBrush(m_worksheet->backgroundFirstColor()));
 				break;
 			}
 		case PlotArea::HorizontalLinearGradient: {
 				QLinearGradient linearGrad(scene_rect.topLeft(), scene_rect.topRight());
 				linearGrad.setColorAt(0, m_worksheet->backgroundFirstColor());
 				linearGrad.setColorAt(1, m_worksheet->backgroundSecondColor());
 				painter->setBrush(QBrush(linearGrad));
 				break;
 			}
 		case PlotArea::VerticalLinearGradient: {
 				QLinearGradient linearGrad(scene_rect.topLeft(), scene_rect.bottomLeft());
 				linearGrad.setColorAt(0, m_worksheet->backgroundFirstColor());
 				linearGrad.setColorAt(1, m_worksheet->backgroundSecondColor());
 				painter->setBrush(QBrush(linearGrad));
 				break;
 			}
 		case PlotArea::TopLeftDiagonalLinearGradient: {
 				QLinearGradient linearGrad(scene_rect.topLeft(), scene_rect.bottomRight());
 				linearGrad.setColorAt(0, m_worksheet->backgroundFirstColor());
 				linearGrad.setColorAt(1, m_worksheet->backgroundSecondColor());
 				painter->setBrush(QBrush(linearGrad));
 				break;
 			}
 		case PlotArea::BottomLeftDiagonalLinearGradient: {
 				QLinearGradient linearGrad(scene_rect.bottomLeft(), scene_rect.topRight());
 				linearGrad.setColorAt(0, m_worksheet->backgroundFirstColor());
 				linearGrad.setColorAt(1, m_worksheet->backgroundSecondColor());
 				painter->setBrush(QBrush(linearGrad));
 				break;
 			}
 		case PlotArea::RadialGradient: {
 				QRadialGradient radialGrad(scene_rect.center(), scene_rect.width()/2);
 				radialGrad.setColorAt(0, m_worksheet->backgroundFirstColor());
 				radialGrad.setColorAt(1, m_worksheet->backgroundSecondColor());
 				painter->setBrush(QBrush(radialGrad));
 				break;
 			}
 			//default:
 			//	painter->setBrush(QBrush(m_worksheet->backgroundFirstColor()));
 		}
 		painter->drawRect(scene_rect);
 	} else if (m_worksheet->backgroundType() == PlotArea::Image) {	// background image
 		const QString& backgroundFileName = m_worksheet->backgroundFileName().trimmed();
 		if ( !backgroundFileName.isEmpty() ) {
 			QPixmap pix(backgroundFileName);
 			switch (m_worksheet->backgroundImageStyle()) {
 			case PlotArea::ScaledCropped:
 				pix = pix.scaled(scene_rect.size().toSize(),Qt::KeepAspectRatioByExpanding,Qt::SmoothTransformation);
 				painter->drawPixmap(scene_rect.topLeft(),pix);
 				break;
 			case PlotArea::Scaled:
 				pix = pix.scaled(scene_rect.size().toSize(),Qt::IgnoreAspectRatio,Qt::SmoothTransformation);
 				painter->drawPixmap(scene_rect.topLeft(),pix);
 				break;
 			case PlotArea::ScaledAspectRatio:
 				pix = pix.scaled(scene_rect.size().toSize(),Qt::KeepAspectRatio,Qt::SmoothTransformation);
 				painter->drawPixmap(scene_rect.topLeft(),pix);
 				break;
 			case PlotArea::Centered:
 				painter->drawPixmap(QPointF(scene_rect.center().x()-pix.size().width()/2,scene_rect.center().y()-pix.size().height()/2),pix);
 				break;
 			case PlotArea::Tiled:
 				painter->drawTiledPixmap(scene_rect,pix);
 				break;
 			case PlotArea::CenterTiled:
 				painter->drawTiledPixmap(scene_rect,pix,QPoint(scene_rect.size().width()/2,scene_rect.size().height()/2));
 				break;
 				//default:
 				//	painter->drawPixmap(scene_rect.topLeft(),pix);
 			}
 		}
 	} else if (m_worksheet->backgroundType() == PlotArea::Pattern) {	// background pattern
 		painter->setBrush(QBrush(m_worksheet->backgroundFirstColor(),m_worksheet->backgroundBrushStyle()));
 		painter->drawRect(scene_rect);
 	}
 
 	//grid
 	if (m_gridSettings.style != WorksheetView::NoGrid) {
 		QColor c = m_gridSettings.color;
 		c.setAlphaF(m_gridSettings.opacity);
 		painter->setPen(c);
 
 		qreal x, y;
 		qreal left = scene_rect.left();
 		qreal right = scene_rect.right();
 		qreal top = scene_rect.top();
 		qreal bottom = scene_rect.bottom();
 
 		if (m_gridSettings.style == WorksheetView::LineGrid) {
 			QLineF line;
 
 			//horizontal lines
 			y = top + m_gridSettings.verticalSpacing;
 			while (y < bottom) {
 				line.setLine( left, y,  right, y );
 				painter->drawLine(line);
 				y += m_gridSettings.verticalSpacing;
 			}
 
 			//vertical lines
 			x = left + m_gridSettings.horizontalSpacing;
 			while (x < right) {
 				line.setLine( x, top,  x, bottom );
 				painter->drawLine(line);
 				x += m_gridSettings.horizontalSpacing;
 			}
 		} else { //DotGrid
 			y = top + m_gridSettings.verticalSpacing;
 			while (y < bottom) {
 				x = left;// + m_gridSettings.horizontalSpacing;
 				while (x < right) {
 					x += m_gridSettings.horizontalSpacing;
 					painter->drawPoint(x, y);
 				}
 				y += m_gridSettings.verticalSpacing;
 			}
 		}
 	}
 }
 
 void WorksheetView::drawBackground(QPainter* painter, const QRectF& rect) {
 	painter->save();
 
 	//painter->setRenderHint(QPainter::Antialiasing);
 	QRectF scene_rect = sceneRect();
 
 	if (!m_worksheet->useViewSize()) {
 		// background
 		KColorScheme scheme(QPalette::Active, KColorScheme::Window);
 		const QColor& color = scheme.background().color();
 		if (!scene_rect.contains(rect))
 			painter->fillRect(rect, color);
 
 		//shadow
 // 		int shadowSize = scene_rect.width()*0.02;
 // 		QRectF rightShadowRect(scene_rect.right(), scene_rect.top() + shadowSize, shadowSize, scene_rect.height());
 // 		QRectF bottomShadowRect(scene_rect.left() + shadowSize, scene_rect.bottom(), scene_rect.width(), shadowSize);
 //
 // 		const QColor& shadeColor = scheme.shade(color, KColorScheme::MidShade);
 // 		painter->fillRect(rightShadowRect.intersected(rect), shadeColor);
 // 		painter->fillRect(bottomShadowRect.intersected(rect), shadeColor);
 	}
 
 	drawBackgroundItems(painter, scene_rect);
 
 	invalidateScene(rect, QGraphicsScene::BackgroundLayer);
 	painter->restore();
 }
 
 bool WorksheetView::isPlotAtPos(QPoint pos) const {
 	bool plot = false;
 	QGraphicsItem* item = itemAt(pos);
 	if (item) {
 		plot = item->data(0).toInt() == WorksheetElement::NameCartesianPlot;
 		if (!plot && item->parentItem())
 			plot = item->parentItem()->data(0).toInt() == WorksheetElement::NameCartesianPlot;
 	}
 
 	return plot;
 }
 
 CartesianPlot* WorksheetView::plotAt(QPoint pos) const {
 	QGraphicsItem* item = itemAt(pos);
 	if (!item)
 		return nullptr;
 
 	QGraphicsItem* plotItem = nullptr;
 	if (item->data(0).toInt() == WorksheetElement::NameCartesianPlot)
 		plotItem = item;
 	else {
 		if (item->parentItem() && item->parentItem()->data(0).toInt() == WorksheetElement::NameCartesianPlot)
 			plotItem = item->parentItem();
 	}
 
 	if (plotItem == nullptr)
 		return nullptr;
 
 	CartesianPlot* plot = nullptr;
 	for (auto* p : m_worksheet->children<CartesianPlot>()) {
 		if (p->graphicsItem() == plotItem) {
 			plot = p;
 			break;
 		}
 	}
 
 	return plot;
 }
 
 //##############################################################################
 //####################################  Events   ###############################
 //##############################################################################
 void WorksheetView::resizeEvent(QResizeEvent *event) {
 	if (m_worksheet->useViewSize())
 		this->processResize();
 
 	QGraphicsView::resizeEvent(event);
 }
 
 void WorksheetView::wheelEvent(QWheelEvent* event) {
 	//https://wiki.qt.io/Smooth_Zoom_In_QGraphicsView
 	if (m_mouseMode == ZoomSelectionMode || m_ctrlPressed) {
 		int numDegrees = event->delta() / 8;
 		int numSteps = numDegrees / 15; // see QWheelEvent documentation
 		zoom(numSteps);
 	} else
 		QGraphicsView::wheelEvent(event);
 }
 
 void WorksheetView::zoom(int numSteps) {
 	m_numScheduledScalings += numSteps;
 	if (m_numScheduledScalings * numSteps < 0) // if user moved the wheel in another direction, we reset previously scheduled scalings
 		m_numScheduledScalings = numSteps;
 
 	auto* anim = new QTimeLine(350, this);
 	anim->setUpdateInterval(20);
 
 	connect(anim, SIGNAL (valueChanged(qreal)), SLOT (scalingTime()));
 	connect(anim, SIGNAL (finished()), SLOT (animFinished()));
 	anim->start();
 }
 
 void WorksheetView::scalingTime() {
 	qreal factor = 1.0 + qreal(m_numScheduledScalings) / 300.0;
 	scale(factor, factor);
 }
 
 void WorksheetView::animFinished() {
 	if (m_numScheduledScalings > 0)
 		m_numScheduledScalings--;
 	else
 		m_numScheduledScalings++;
 	sender()->~QObject();
 }
 
 void WorksheetView::mousePressEvent(QMouseEvent* event) {
 	//prevent the deselection of items when context menu event
 	//was triggered (right button click)
 	if (event->button() == Qt::RightButton) {
 		event->accept();
 		return;
 	}
 
 	if (event->button() == Qt::LeftButton && m_mouseMode == ZoomSelectionMode) {
 		m_selectionStart = event->pos();
 		m_selectionEnd = m_selectionStart; //select&zoom'g starts -> reset the end point to the start point
 		m_selectionBandIsShown = true;
 		QGraphicsView::mousePressEvent(event);
 		return;
 	}
 
 	//to select curves having overlapping bounding boxes we need to check whether the cursor
 	//is inside of item's shapes and not inside of the bounding boxes (Qt's default behaviour).
 	for (auto* item : items(event->pos())) {
 		if (!dynamic_cast<XYCurvePrivate*>(item))
 			continue;
 
 		if ( item->shape().contains(item->mapFromScene(mapToScene(event->pos()))) ) {
 			//deselect currently selected items
 			for (auto* selectedItem : scene()->selectedItems())
 				selectedItem->setSelected(false);
 
 			//select the item under the cursor and update the current selection
 			item->setSelected(true);
 			selectionChanged();
 
 			return;
 		}
 	}
 
 	// select the worksheet in the project explorer if the view was clicked
 	// and there is no selection currently. We need this for the case when
 	// there is a single worksheet in the project and we change from the project-node
 	// in the project explorer to the worksheet-node by clicking the view.
 	if ( scene()->selectedItems().isEmpty() )
 		m_worksheet->setSelectedInView(true);
 
 	QGraphicsView::mousePressEvent(event);
 }
 
 void WorksheetView::mouseReleaseEvent(QMouseEvent* event) {
 	if (event->button() == Qt::LeftButton && m_mouseMode == ZoomSelectionMode) {
 		m_selectionBandIsShown = false;
 		viewport()->repaint(QRect(m_selectionStart, m_selectionEnd).normalized());
 
 		//don't zoom if very small region was selected, avoid occasional/unwanted zooming
 		m_selectionEnd = event->pos();
 		if ( abs(m_selectionEnd.x() - m_selectionStart.x()) > 20 && abs(m_selectionEnd.y() - m_selectionStart.y()) > 20 )
 			fitInView(mapToScene(QRect(m_selectionStart, m_selectionEnd).normalized()).boundingRect(), Qt::KeepAspectRatio);
 	}
 
 	QGraphicsView::mouseReleaseEvent(event);
 }
 
 void WorksheetView::mouseMoveEvent(QMouseEvent* event) {
 	if (m_mouseMode == SelectionMode && m_cartesianPlotMouseMode != CartesianPlot::SelectionMode ) {
 		//check whether there is a cartesian plot under the cursor
 		//and set the cursor appearance according to the current mouse mode for the cartesian plots
 		if ( isPlotAtPos(event->pos()) ) {
 			if (m_cartesianPlotMouseMode == CartesianPlot::ZoomSelectionMode)
 				setCursor(Qt::CrossCursor);
 			else if (m_cartesianPlotMouseMode == CartesianPlot::ZoomXSelectionMode)
 				setCursor(Qt::SizeHorCursor);
 			else if (m_cartesianPlotMouseMode == CartesianPlot::ZoomYSelectionMode)
 				setCursor(Qt::SizeVerCursor);
 		} else
 			setCursor(Qt::ArrowCursor);
 	} else if (m_mouseMode == SelectionMode && m_cartesianPlotMouseMode == CartesianPlot::SelectionMode )
 		setCursor(Qt::ArrowCursor);
 	else if (m_selectionBandIsShown) {
 		QRect rect = QRect(m_selectionStart, m_selectionEnd).normalized();
 		m_selectionEnd = event->pos();
 		rect = rect.united(QRect(m_selectionStart, m_selectionEnd).normalized());
 		qreal penWidth = 5/transform().m11();
 		rect.setX(rect.x()-penWidth);
 		rect.setY(rect.y()-penWidth);
 		rect.setHeight(rect.height()+2*penWidth);
 		rect.setWidth(rect.width()+2*penWidth);
 		viewport()->repaint(rect);
 	}
 
 	//show the magnification window
 	if (magnificationFactor /*&& m_mouseMode == SelectAndEditMode*/) {
 		if (!m_magnificationWindow) {
 			m_magnificationWindow = new QGraphicsPixmapItem(nullptr);
 			m_magnificationWindow->setZValue(std::numeric_limits<int>::max());
 			scene()->addItem(m_magnificationWindow);
 		}
 
 		m_magnificationWindow->setVisible(false);
 
 		//copy the part of the view to be shown magnified
 		QPointF pos = mapToScene(event->pos());
 		const int size = Worksheet::convertToSceneUnits(2.0, Worksheet::Centimeter)/transform().m11();
 
 		const QRectF copyRect(pos.x() - size/(2*magnificationFactor), pos.y() - size/(2*magnificationFactor), size/magnificationFactor, size/magnificationFactor);
 		QPixmap px = QPixmap::grabWidget(this, mapFromScene(copyRect).boundingRect());
 		px = px.scaled(size, size, Qt::IgnoreAspectRatio, Qt::SmoothTransformation);
 
 		//draw the bounding rect
 		QPainter painter(&px);
 		const QPen pen = QPen(Qt::lightGray, 2/transform().m11());
 		painter.setPen(pen);
 		QRect rect = px.rect();
 		rect.setWidth(rect.width()-pen.widthF()/2);
 		rect.setHeight(rect.height()-pen.widthF()/2);
 		painter.drawRect(rect);
 
 		//set the pixmap
 		m_magnificationWindow->setPixmap(px);
 		m_magnificationWindow->setPos(pos.x()- px.width()/2, pos.y()- px.height()/2);
 
 		m_magnificationWindow->setVisible(true);
 	} else if (m_magnificationWindow)
 		m_magnificationWindow->setVisible(false);
 
 	QGraphicsView::mouseMoveEvent(event);
 }
 
 void WorksheetView::contextMenuEvent(QContextMenuEvent* e) {
 	if ( (m_magnificationWindow && m_magnificationWindow->isVisible() && items(e->pos()).size() == 1) || !itemAt(e->pos()) ) {
 		//no item or only the magnification window under the cursor -> show the context menu for the worksheet
 		QMenu *menu = new QMenu(this);
 		this->createContextMenu(menu);
 		menu->exec(QCursor::pos());
 	} else {
 		//propagate the event to the scene and graphics items
 		QGraphicsView::contextMenuEvent(e);
 	}
 }
 
 void WorksheetView::keyPressEvent(QKeyEvent* event) {
 	if (event->matches(QKeySequence::Copy)) {
 		//add here copying of objects
 		exportToClipboard();
 	} else {
 		if (event->key() == Qt::Key_Control)
 			m_ctrlPressed = true;
 	}
 
 	QGraphicsView::keyPressEvent(event);
 }
 
 void WorksheetView::keyReleaseEvent(QKeyEvent* event) {
 	m_ctrlPressed = false;
 	QGraphicsView::keyReleaseEvent(event);
 }
 
 void WorksheetView::dragEnterEvent(QDragEnterEvent* event) {
 	//ignore events not related to internal drags of columns etc., e.g. dropping of external files onto LabPlot
 	const QMimeData* mimeData = event->mimeData();
 	if (!mimeData) {
 		event->ignore();
 		return;
 	}
 
 	if (mimeData->formats().at(0) != QLatin1String("labplot-dnd")) {
 		event->ignore();
 		return;
 	}
 
 	//select the worksheet in the project explorer and bring the view to the foreground
 	m_worksheet->setSelectedInView(true);
 	m_worksheet->mdiSubWindow()->mdiArea()->setActiveSubWindow(m_worksheet->mdiSubWindow());
 
 	event->setAccepted(true);
 }
 
 void WorksheetView::dragMoveEvent(QDragMoveEvent* event) {
 	// only accept drop events if we have a plot under the cursor where we can drop columns onto
 	bool plot = isPlotAtPos(event->pos());
 	event->setAccepted(plot);
 }
 
 void WorksheetView::dropEvent(QDropEvent* event) {
 	CartesianPlot* plot = plotAt(event->pos());
 	if (plot != nullptr)
 		plot->processDropEvent(event);
 }
 
 //##############################################################################
 //####################################  SLOTs   ################################
 //##############################################################################
 void WorksheetView::useViewSizeRequested() {
 	if (m_worksheet->useViewSize()) {
 		setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
 		setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
 		zoomFitPageHeightAction->setVisible(false);
 		zoomFitPageWidthAction->setVisible(false);
 		currentZoomAction = zoomInViewAction;
 		if (tbZoom)
 			tbZoom->setDefaultAction(zoomInViewAction);
 
 		//determine and set the current view size
 		this->processResize();
 	} else {
 		setHorizontalScrollBarPolicy(Qt::ScrollBarAsNeeded);
 		setVerticalScrollBarPolicy(Qt::ScrollBarAsNeeded);
 		zoomFitPageHeightAction->setVisible(true);
 		zoomFitPageWidthAction->setVisible(true);
 	}
 }
 
 void WorksheetView::processResize() {
 	if (size() != sceneRect().size()) {
 		static const float hscale = QApplication::desktop()->physicalDpiX()/(Worksheet::convertToSceneUnits(1,Worksheet::Inch));
 		static const float vscale = QApplication::desktop()->physicalDpiY()/(Worksheet::convertToSceneUnits(1,Worksheet::Inch));
 		m_worksheet->setUndoAware(false);
 		m_worksheet->setPageRect(QRectF(0.0, 0.0, width()/hscale, height()/vscale));
 		m_worksheet->setUndoAware(true);
 	}
 }
 
 void WorksheetView::changeZoom(QAction* action) {
 	if (action == zoomInViewAction)
 		zoom(1);
 	else if (action == zoomOutViewAction)
 		zoom(-1);
 	else if (action == zoomOriginAction) {
 		static const float hscale = QApplication::desktop()->physicalDpiX()/(Worksheet::convertToSceneUnits(1,Worksheet::Inch));
 		static const float vscale = QApplication::desktop()->physicalDpiY()/(Worksheet::convertToSceneUnits(1,Worksheet::Inch));
 		setTransform(QTransform::fromScale(hscale, vscale));
 	} else if (action == zoomFitPageWidthAction) {
 		float scaleFactor = viewport()->width()/scene()->sceneRect().width();
 		setTransform(QTransform::fromScale(scaleFactor, scaleFactor));
 	} else if (action == zoomFitPageHeightAction) {
 		float scaleFactor = viewport()->height()/scene()->sceneRect().height();
 		setTransform(QTransform::fromScale(scaleFactor, scaleFactor));
 	} else if (action == zoomFitSelectionAction)
 		fitInView(scene()->selectionArea().boundingRect(),Qt::KeepAspectRatio);
 	currentZoomAction = action;
 	if (tbZoom)
 		tbZoom->setDefaultAction(action);
 }
 
 void WorksheetView::magnificationChanged(QAction* action) {
 	if (action == noMagnificationAction)
 		magnificationFactor = 0;
 	else if (action == twoTimesMagnificationAction)
 		magnificationFactor = 2;
 	else if (action == threeTimesMagnificationAction)
 		magnificationFactor = 3;
 	else if (action == fourTimesMagnificationAction)
 		magnificationFactor = 4;
 	else if (action == fiveTimesMagnificationAction)
 		magnificationFactor = 5;
 
 	currentMagnificationAction = action;
 	if (tbMagnification)
 		tbMagnification->setDefaultAction(action);
 }
 
 void WorksheetView::mouseModeChanged(QAction* action) {
 	if (action == selectionModeAction) {
 		m_mouseMode = SelectionMode;
 		setInteractive(true);
 		setDragMode(QGraphicsView::NoDrag);
 	} else if (action == navigationModeAction) {
 		m_mouseMode = NavigationMode;
 		setInteractive(false);
 		setDragMode(QGraphicsView::ScrollHandDrag);
 	} else {
 		m_mouseMode = ZoomSelectionMode;
 		setInteractive(false);
 		setDragMode(QGraphicsView::NoDrag);
 	}
 }
 
 //"Add new" related slots
 void WorksheetView::addNew(QAction* action) {
 	WorksheetElement* aspect = nullptr;
 	if (action == addCartesianPlot1Action) {
 		CartesianPlot* plot = new CartesianPlot(i18n("xy-plot"));
 		plot->initDefault(CartesianPlot::FourAxes);
 		plot->setMouseMode(m_cartesianPlotMouseMode);
 		aspect = plot;
 		if (tbNewCartesianPlot)
 			tbNewCartesianPlot->setDefaultAction(addCartesianPlot1Action);
 	} else if (action == addCartesianPlot2Action) {
 		CartesianPlot* plot = new CartesianPlot(i18n("xy-plot"));
 		plot->initDefault(CartesianPlot::TwoAxes);
 		plot->setMouseMode(m_cartesianPlotMouseMode);
 		aspect = plot;
 		if (tbNewCartesianPlot)
 			tbNewCartesianPlot->setDefaultAction(addCartesianPlot2Action);
 	} else if (action == addCartesianPlot3Action) {
 		CartesianPlot* plot = new CartesianPlot(i18n("xy-plot"));
 		plot->initDefault(CartesianPlot::TwoAxesCentered);
 		plot->setMouseMode(m_cartesianPlotMouseMode);
 		aspect = plot;
 		if (tbNewCartesianPlot)
 			tbNewCartesianPlot->setDefaultAction(addCartesianPlot3Action);
 	} else if (action == addCartesianPlot4Action) {
 		CartesianPlot* plot = new CartesianPlot(i18n("xy-plot"));
 		plot->initDefault(CartesianPlot::TwoAxesCenteredZero);
 		plot->setMouseMode(m_cartesianPlotMouseMode);
 		aspect = plot;
 		if (tbNewCartesianPlot)
 			tbNewCartesianPlot->setDefaultAction(addCartesianPlot4Action);
 	} else if (action == addTextLabelAction) {
 		TextLabel* l = new TextLabel(i18n("Text Label"));
 		l->setText(i18n("Text Label"));
 		aspect = l;
 	}
 	if (!aspect)
 		return;
 
 	m_worksheet->addChild(aspect);
 	handleCartesianPlotActions();
 
 	if (!m_fadeInTimeLine) {
 		m_fadeInTimeLine = new QTimeLine(1000, this);
 		m_fadeInTimeLine->setFrameRange(0, 100);
 		connect(m_fadeInTimeLine, SIGNAL(valueChanged(qreal)), this, SLOT(fadeIn(qreal)));
 	}
 
 	//if there is already an element fading in, stop the time line and show the element with the full opacity.
 	if (m_fadeInTimeLine->state() == QTimeLine::Running) {
 		m_fadeInTimeLine->stop();
 		auto* effect = new QGraphicsOpacityEffect();
 		effect->setOpacity(1);
 		lastAddedWorksheetElement->graphicsItem()->setGraphicsEffect(effect);
 	}
 
 	//fade-in the newly added element
 	lastAddedWorksheetElement = aspect;
 	auto* effect = new QGraphicsOpacityEffect();
 	effect->setOpacity(0);
 	lastAddedWorksheetElement->graphicsItem()->setGraphicsEffect(effect);
 	m_fadeInTimeLine->start();
 }
 
 /*!
  * select all top-level items
  */
 void WorksheetView::selectAllElements() {
 	//deselect all previously selected items since there can be some non top-level items belong them
 	m_suppressSelectionChangedEvent = true;
 	for (auto* item : m_selectedItems)
 		m_worksheet->setItemSelectedInView(item, false);
 
 	//select top-level items
 	for (auto* item : scene()->items()) {
 		if (!item->parentItem())
 			item->setSelected(true);
 	}
 	m_suppressSelectionChangedEvent = false;
 	this->selectionChanged();
 }
 
 /*!
  * deletes selected worksheet elements
  */
 void WorksheetView::deleteElement() {
 	if (m_selectedItems.isEmpty())
 		return;
 
 	int rc = KMessageBox::warningYesNo( this,
 	                                    i18np("Do you really want to delete the selected object?", "Do you really want to delete the selected %1 objects?", m_selectedItems.size()),
 	                                    i18np("Delete selected object", "Delete selected objects", m_selectedItems.size()));
 
 	if (rc == KMessageBox::No)
 		return;
 
 	m_suppressSelectionChangedEvent = true;
 	m_worksheet->beginMacro(i18n("%1: Remove selected worksheet elements.", m_worksheet->name()));
 	for (auto* item : m_selectedItems)
 		m_worksheet->deleteAspectFromGraphicsItem(item);
 	m_worksheet->endMacro();
 	m_suppressSelectionChangedEvent = false;
 }
 
 void WorksheetView::aspectAboutToBeRemoved(const AbstractAspect* aspect) {
 	lastAddedWorksheetElement = dynamic_cast<WorksheetElement*>(const_cast<AbstractAspect*>(aspect));
 	if (!lastAddedWorksheetElement)
 		return;
 
 	//FIXME: fading-out doesn't work
 	//also, the following code collides with undo/redo of the deletion
 	//of a worksheet element (after redoing the element is not shown with the full opacity
 	/*
 		if (!m_fadeOutTimeLine) {
 			m_fadeOutTimeLine = new QTimeLine(1000, this);
 			m_fadeOutTimeLine->setFrameRange(0, 100);
 			connect(m_fadeOutTimeLine, SIGNAL(valueChanged(qreal)), this, SLOT(fadeOut(qreal)));
 		}
 
 		//if there is already an element fading out, stop the time line
 		if (m_fadeOutTimeLine->state() == QTimeLine::Running)
 			m_fadeOutTimeLine->stop();
 
 		m_fadeOutTimeLine->start();
 	*/
 }
 
 void WorksheetView::fadeIn(qreal value) {
 	auto* effect = new QGraphicsOpacityEffect();
 	effect->setOpacity(value);
 	lastAddedWorksheetElement->graphicsItem()->setGraphicsEffect(effect);
 }
 
 void WorksheetView::fadeOut(qreal value) {
 	auto* effect = new QGraphicsOpacityEffect();
 	effect->setOpacity(1 - value);
 	lastAddedWorksheetElement->graphicsItem()->setGraphicsEffect(effect);
 }
 
 /*!
  * called when one of the layout-actions in WorkseetView was triggered.
  * sets the layout in Worksheet and enables/disables the layout actions.
  */
 void WorksheetView::changeLayout(QAction* action) {
 	if (action == breakLayoutAction) {
 		verticalLayoutAction->setEnabled(true);
 		verticalLayoutAction->setChecked(false);
 
 		horizontalLayoutAction->setEnabled(true);
 		horizontalLayoutAction->setChecked(false);
 
 		gridLayoutAction->setEnabled(true);
 		gridLayoutAction->setChecked(false);
 
 		breakLayoutAction->setEnabled(false);
 
 		m_worksheet->setLayout(Worksheet::NoLayout);
 	} else {
 		verticalLayoutAction->setEnabled(false);
 		horizontalLayoutAction->setEnabled(false);
 		gridLayoutAction->setEnabled(false);
 		breakLayoutAction->setEnabled(true);
 
 		if (action == verticalLayoutAction) {
 			verticalLayoutAction->setChecked(true);
 			m_worksheet->setLayout(Worksheet::VerticalLayout);
 		} else if (action == horizontalLayoutAction) {
 			horizontalLayoutAction->setChecked(true);
 			m_worksheet->setLayout(Worksheet::HorizontalLayout);
 		} else {
 			gridLayoutAction->setChecked(true);
 			m_worksheet->setLayout(Worksheet::GridLayout);
 		}
 	}
 }
 
 void WorksheetView::changeGrid(QAction* action) {
 	if (action == noGridAction) {
 		m_gridSettings.style = WorksheetView::NoGrid;
 		snapToGridAction->setEnabled(false);
 	} else if (action == sparseLineGridAction) {
 		m_gridSettings.style = WorksheetView::LineGrid;
 		m_gridSettings.color = Qt::gray;
 		m_gridSettings.opacity = 0.7;
 		m_gridSettings.horizontalSpacing = 15;
 		m_gridSettings.verticalSpacing = 15;
 	} else if (action == denseLineGridAction) {
 		m_gridSettings.style = WorksheetView::LineGrid;
 		m_gridSettings.color = Qt::gray;
 		m_gridSettings.opacity = 0.7;
 		m_gridSettings.horizontalSpacing = 5;
 		m_gridSettings.verticalSpacing = 5;
 	} else if (action == denseDotGridAction) {
 		m_gridSettings.style = WorksheetView::DotGrid;
 		m_gridSettings.color = Qt::black;
 		m_gridSettings.opacity = 0.7;
 		m_gridSettings.horizontalSpacing = 5;
 		m_gridSettings.verticalSpacing = 5;
 	} else if (action == sparseDotGridAction) {
 		m_gridSettings.style = WorksheetView::DotGrid;
 		m_gridSettings.color = Qt::black;
 		m_gridSettings.opacity = 0.7;
 		m_gridSettings.horizontalSpacing = 15;
 		m_gridSettings.verticalSpacing = 15;
 	} else if (action == customGridAction) {
 		auto* dlg = new GridDialog(this);
 		if (dlg->exec() == QDialog::Accepted)
 			dlg->save(m_gridSettings);
 		else
 			return;
 	}
 
 	if (m_gridSettings.style == WorksheetView::NoGrid)
 		snapToGridAction->setEnabled(false);
 	else
 		snapToGridAction->setEnabled(true);
 
 	invalidateScene(sceneRect(), QGraphicsScene::BackgroundLayer);
 }
 
 //TODO
 void WorksheetView::changeSnapToGrid() {
 
 }
 
 /*!
  *  Selects the QGraphicsItem \c item in \c WorksheetView.
  * 	The selection in \c ProjectExplorer is forwarded to  \c Worksheet
  *  and is finally handled here.
  */
 void WorksheetView::selectItem(QGraphicsItem* item) {
 	m_suppressSelectionChangedEvent = true;
 	item->setSelected(true);
 	m_selectedItems<<item;
 	handleCartesianPlotActions();
 	m_suppressSelectionChangedEvent = false;
 }
 
 /*!
  *  Deselects the \c QGraphicsItem \c item in \c WorksheetView.
  * 	The deselection in \c ProjectExplorer is forwarded to \c Worksheet
  *  and is finally handled here.
  */
 void WorksheetView::deselectItem(QGraphicsItem* item) {
 	m_suppressSelectionChangedEvent = true;
 	item->setSelected(false);
 	m_selectedItems.removeOne(item);
 	handleCartesianPlotActions();
 	m_suppressSelectionChangedEvent = false;
 }
 
 /*!
  *  Called on selection changes in the view.
  *   Determines which items were selected and deselected
  *  and forwards these changes to \c Worksheet
  */
 void WorksheetView::selectionChanged() {
 	//if the project is being closed, the scene items are being removed and the selection can change.
 	//don't react on these changes since this can lead crashes (worksheet object is already in the destructor).
 	if (m_isClosing)
 		return;
 
 	if (m_suppressSelectionChangedEvent)
 		return;
 
 	QList<QGraphicsItem*> items = scene()->selectedItems();
 
 	//When making a graphics item invisible, it gets deselected in the scene.
 	//In this case we don't want to deselect the item in the project explorer.
 	bool invisibleDeselected = false;
 
 	//check, whether the previously selected items were deselected now.
 	//Forward the deselection prior to the selection of new items
 	//in order to avoid the unwanted multiple selection in project explorer
 	for (auto* item : m_selectedItems ) {
 		if ( items.indexOf(item) == -1 ) {
 			if (item->isVisible())
 				m_worksheet->setItemSelectedInView(item, false);
 			else
 				invisibleDeselected = true;
 		}
 	}
 
 	//select new items
 	if (items.isEmpty() && invisibleDeselected == false) {
 		//no items selected -> select the worksheet again.
 		m_worksheet->setSelectedInView(true);
 
 		//if one of the "zoom&select" plot mouse modes was selected before, activate the default "selection mode" again
 		//since no plots are selected now.
 		if (m_mouseMode == SelectionMode && m_cartesianPlotMouseMode!= CartesianPlot::SelectionMode) {
 			cartesianPlotSelectionModeAction->setChecked(true);
 			cartesianPlotMouseModeChanged(cartesianPlotSelectionModeAction);
 		}
 	} else {
 		for (const auto* item : items)
 			m_worksheet->setItemSelectedInView(item, true);
 
 		//items selected -> deselect the worksheet in the project explorer
 		//prevents unwanted multiple selection with worksheet (if it was selected before)
 		m_worksheet->setSelectedInView(false);
 	}
 
 	m_selectedItems = items;
 	handleCartesianPlotActions();
 }
 
 //check whether we have cartesian plots selected and activate/deactivate
 void WorksheetView::handleCartesianPlotActions() {
 	if (!m_menusInitialized)
 		return;
 
 	bool plot = false;
 	if (m_worksheet->cartesianPlotActionMode() == Worksheet::CartesianPlotActionMode::ApplyActionToSelection) {
 		//check whether we have cartesian plots selected
 		for (auto* item : m_selectedItems) {
 			//TODO: or if a children of a plot is selected
 			if (item->data(0).toInt() == WorksheetElement::NameCartesianPlot) {
 				plot = true;
 				break;
 			}
 		}
 	} else {
 		//actions are applied to all available plots -> check whether we have plots
 		plot = (m_worksheet->children<CartesianPlot>().size() != 0);
 	}
 
 	cartesianPlotSelectionModeAction->setEnabled(plot);
 	cartesianPlotZoomSelectionModeAction->setEnabled(plot);
 	cartesianPlotZoomXSelectionModeAction->setEnabled(plot);
 	cartesianPlotZoomYSelectionModeAction->setEnabled(plot);
 
 	addCurveAction->setEnabled(plot);
+	addHistogramAction->setEnabled(plot);
 	addEquationCurveAction->setEnabled(plot);
 	addDataOperationCurveAction->setEnabled(false);
 	addDataReductionCurveAction->setEnabled(plot);
 	addDifferentiationCurveAction->setEnabled(plot);
 	addIntegrationCurveAction->setEnabled(plot);
 	addInterpolationCurveAction->setEnabled(plot);
 	addSmoothCurveAction->setEnabled(plot);
 	addFitCurveAction->setEnabled(plot);
 	addFourierFilterCurveAction->setEnabled(plot);
 	addFourierTransformCurveAction->setEnabled(plot);
 	addConvolutionCurveAction->setEnabled(plot);
 	addCorrelationCurveAction->setEnabled(plot);
 
 	addHorizontalAxisAction->setEnabled(plot);
 	addVerticalAxisAction->setEnabled(plot);
 	addLegendAction->setEnabled(plot);
 
 	scaleAutoXAction->setEnabled(plot);
 	scaleAutoYAction->setEnabled(plot);
 	scaleAutoAction->setEnabled(plot);
 	zoomInAction->setEnabled(plot);
 	zoomOutAction->setEnabled(plot);
 	zoomInXAction->setEnabled(plot);
 	zoomOutXAction->setEnabled(plot);
 	zoomInYAction->setEnabled(plot);
 	zoomOutYAction->setEnabled(plot);
 	shiftLeftXAction->setEnabled(plot);
 	shiftRightXAction->setEnabled(plot);
 	shiftUpYAction->setEnabled(plot);
 	shiftDownYAction->setEnabled(plot);
 
 	// analysis menu
 	//TODO: enable also if children of plots are selected
 	addDataOperationAction->setEnabled(false);
 	m_dataManipulationMenu->setEnabled(plot);
 	addDifferentiationAction->setEnabled(plot);
 	addIntegrationAction->setEnabled(plot);
 	addInterpolationAction->setEnabled(plot);
 	addSmoothAction->setEnabled(plot);
 	addFitAction->setEnabled(plot);
 	addFourierFilterAction->setEnabled(plot);
 	addFourierTransformAction->setEnabled(plot);
 	addConvolutionAction->setEnabled(plot);
 	addCorrelationAction->setEnabled(plot);
 }
 
 void WorksheetView::exportToFile(const QString& path, const ExportFormat format, const ExportArea area, const bool background, const int resolution) {
 	QRectF sourceRect;
 
 	//determine the rectangular to print
 	if (area == WorksheetView::ExportBoundingBox)
 		sourceRect = scene()->itemsBoundingRect();
 	else if (area == WorksheetView::ExportSelection) {
 		//TODO doesn't work: rect = scene()->selectionArea().boundingRect();
 		for (const auto* item : m_selectedItems)
 			sourceRect = sourceRect.united( item->mapToScene(item->boundingRect()).boundingRect() );
 	} else
 		sourceRect = scene()->sceneRect();
 
 	//print
 	if (format == WorksheetView::Pdf) {
 		QPrinter printer(QPrinter::HighResolution);
 		printer.setOutputFormat(QPrinter::PdfFormat);
 
 		printer.setOutputFileName(path);
 		int w = Worksheet::convertFromSceneUnits(sourceRect.width(), Worksheet::Millimeter);
 		int h = Worksheet::convertFromSceneUnits(sourceRect.height(), Worksheet::Millimeter);
 		printer.setPaperSize( QSizeF(w, h), QPrinter::Millimeter);
 		printer.setPageMargins(0,0,0,0, QPrinter::Millimeter);
 		printer.setPrintRange(QPrinter::PageRange);
 		printer.setCreator(QLatin1String("LabPlot ") + LVERSION);
 
 		QPainter painter(&printer);
 		painter.setRenderHint(QPainter::Antialiasing);
 		QRectF targetRect(0, 0, painter.device()->width(),painter.device()->height());
 		painter.begin(&printer);
 		exportPaint(&painter, targetRect, sourceRect, background);
 		painter.end();
 	} else if (format == WorksheetView::Svg) {
 		QSvgGenerator generator;
 		generator.setFileName(path);
 		int w = Worksheet::convertFromSceneUnits(sourceRect.width(), Worksheet::Millimeter);
 		int h = Worksheet::convertFromSceneUnits(sourceRect.height(), Worksheet::Millimeter);
 		w = w*QApplication::desktop()->physicalDpiX()/25.4;
 		h = h*QApplication::desktop()->physicalDpiY()/25.4;
 
 		generator.setSize(QSize(w, h));
 		QRectF targetRect(0, 0, w, h);
 		generator.setViewBox(targetRect);
 
 		QPainter painter;
 		painter.begin(&generator);
 		exportPaint(&painter, targetRect, sourceRect, background);
 		painter.end();
 	} else {
 		//PNG
 		//TODO add all formats supported by Qt in QImage
 		int w = Worksheet::convertFromSceneUnits(sourceRect.width(), Worksheet::Millimeter);
 		int h = Worksheet::convertFromSceneUnits(sourceRect.height(), Worksheet::Millimeter);
 		w = w*resolution/25.4;
 		h = h*resolution/25.4;
 		QImage image(QSize(w, h), QImage::Format_ARGB32_Premultiplied);
 		image.fill(Qt::transparent);
 		QRectF targetRect(0, 0, w, h);
 
 		QPainter painter;
 		painter.begin(&image);
 		painter.setRenderHint(QPainter::Antialiasing);
 		exportPaint(&painter, targetRect, sourceRect, background);
 		painter.end();
 
 		image.save(path, "PNG");
 	}
 }
 
 void WorksheetView::exportToClipboard() {
 #ifndef QT_NO_CLIPBOARD
 	QRectF sourceRect;
 
 	if (m_selectedItems.size() == 0)
 		sourceRect = scene()->itemsBoundingRect();
 	else {
 		//export selection
 		for (const auto* item : m_selectedItems)
 			sourceRect = sourceRect.united( item->mapToScene(item->boundingRect()).boundingRect() );
 	}
 
 	int w = Worksheet::convertFromSceneUnits(sourceRect.width(), Worksheet::Millimeter);
 	int h = Worksheet::convertFromSceneUnits(sourceRect.height(), Worksheet::Millimeter);
 	w = w*QApplication::desktop()->physicalDpiX()/25.4;
 	h = h*QApplication::desktop()->physicalDpiY()/25.4;
 	QImage image(QSize(w, h), QImage::Format_ARGB32_Premultiplied);
 	image.fill(Qt::transparent);
 	QRectF targetRect(0, 0, w, h);
 
 	QPainter painter;
 	painter.begin(&image);
 	painter.setRenderHint(QPainter::Antialiasing);
 	exportPaint(&painter, targetRect, sourceRect, true);
 	painter.end();
 
 	QClipboard* clipboard = QApplication::clipboard();
 	clipboard->setImage(image, QClipboard::Clipboard);
 #endif
 }
 
 void WorksheetView::exportPaint(QPainter* painter, const QRectF& targetRect, const QRectF& sourceRect, const bool background) {
 	//draw the background
 	if (background) {
 		painter->save();
 		painter->scale(targetRect.width()/sourceRect.width(), targetRect.height()/sourceRect.height());
 		drawBackground(painter, sourceRect);
 		painter->restore();
 	}
 
 	//draw the scene items
 	m_worksheet->setPrinting(true);
 	scene()->render(painter, QRectF(), sourceRect);
 	m_worksheet->setPrinting(false);
 }
 
 void WorksheetView::print(QPrinter* printer) {
 	m_worksheet->setPrinting(true);
 	QPainter painter(printer);
 	painter.setRenderHint(QPainter::Antialiasing);
 	// draw background
 	QRectF page_rect = printer->pageRect();
 	QRectF scene_rect = scene()->sceneRect();
 	//qDebug()<<"source (scene):"<<scene_rect;
 	//qDebug()<<"target (page):"<<page_rect;
 	float scale = qMax(scene_rect.width()/page_rect.width(),scene_rect.height()/page_rect.height());
 	//qDebug()<<"scale ="<<scale;
 	//qDebug()<<"background size ="<<scene_rect.width()/scale<<scene_rect.height()/scale;
 	drawBackgroundItems(&painter, QRectF(0,0,scene_rect.width()/scale,scene_rect.height()/scale));
 	// draw scene
 	scene()->render(&painter);
 	m_worksheet->setPrinting(false);
 }
 
 void WorksheetView::updateBackground() {
 	invalidateScene(sceneRect(), QGraphicsScene::BackgroundLayer);
 }
 
 /*!
  * called when the layout was changed in Worksheet,
  * enables the corresponding action
  */
 void WorksheetView::layoutChanged(Worksheet::Layout layout) {
 	if (layout == Worksheet::NoLayout) {
 		verticalLayoutAction->setEnabled(true);
 		verticalLayoutAction->setChecked(false);
 
 		horizontalLayoutAction->setEnabled(true);
 		horizontalLayoutAction->setChecked(false);
 
 		gridLayoutAction->setEnabled(true);
 		gridLayoutAction->setChecked(false);
 
 		breakLayoutAction->setEnabled(false);
 	} else {
 		verticalLayoutAction->setEnabled(false);
 		horizontalLayoutAction->setEnabled(false);
 		gridLayoutAction->setEnabled(false);
 		breakLayoutAction->setEnabled(true);
 
 		if (layout == Worksheet::VerticalLayout)
 			verticalLayoutAction->setChecked(true);
 		else if (layout == Worksheet::HorizontalLayout)
 			horizontalLayoutAction->setChecked(true);
 		else
 			gridLayoutAction->setChecked(true);
 	}
 }
 
 
 //##############################################################################
 //########################  SLOTs for cartesian plots   ########################
 //##############################################################################
 void WorksheetView::cartesianPlotActionModeChanged(QAction* action) {
 	if (action == cartesianPlotApplyToSelectionAction)
 		m_worksheet->setCartesianPlotActionMode(Worksheet::CartesianPlotActionMode::ApplyActionToSelection);
 	else
 		m_worksheet->setCartesianPlotActionMode(Worksheet::CartesianPlotActionMode::ApplyActionToAll);
 
 	handleCartesianPlotActions();
 }
 
 void WorksheetView::plotsLockedActionChanged(bool checked) {
 	m_worksheet->setPlotsLocked(checked);
 }
 
 void WorksheetView::cartesianPlotMouseModeChanged(QAction* action) {
 	if (action == cartesianPlotSelectionModeAction)
 		m_cartesianPlotMouseMode = CartesianPlot::SelectionMode;
 	else if (action == cartesianPlotZoomSelectionModeAction)
 		m_cartesianPlotMouseMode = CartesianPlot::ZoomSelectionMode;
 	else if (action == cartesianPlotZoomXSelectionModeAction)
 		m_cartesianPlotMouseMode = CartesianPlot::ZoomXSelectionMode;
 	else if (action == cartesianPlotZoomYSelectionModeAction)
 		m_cartesianPlotMouseMode = CartesianPlot::ZoomYSelectionMode;
 
 	for (auto* plot : m_worksheet->children<CartesianPlot>() )
 		plot->setMouseMode(m_cartesianPlotMouseMode);
 }
 
 void WorksheetView::cartesianPlotAddNew(QAction* action) {
 	QVector<CartesianPlot*> plots = m_worksheet->children<CartesianPlot>();
 	if (m_worksheet->cartesianPlotActionMode() == Worksheet::ApplyActionToSelection) {
 		int selectedPlots = 0;
 		for (auto* plot : plots) {
 			if (m_selectedItems.indexOf(plot->graphicsItem()) != -1)
 				++selectedPlots;
 		}
 
 		if  (selectedPlots > 1)
 			m_worksheet->beginMacro(i18n("%1: Add curve to %2 plots", m_worksheet->name(), selectedPlots));
 
 		for (auto* plot : plots) {
 			//TODO: or if any children of a plot is selected
 			if (m_selectedItems.indexOf(plot->graphicsItem()) != -1)
 				this->cartesianPlotAdd(plot, action);
 		}
 
 		if (selectedPlots > 1)
 			m_worksheet->endMacro();
 	} else {
 		if  (plots.size() > 1)
 			m_worksheet->beginMacro(i18n("%1: Add curve to %2 plots", m_worksheet->name(), plots.size()));
 
 		for (auto* plot : plots)
 			this->cartesianPlotAdd(plot, action);
 
 		if  (plots.size() > 1)
 			m_worksheet->endMacro();
 	}
 }
 
 void WorksheetView::cartesianPlotAdd(CartesianPlot* plot, QAction* action) {
 	DEBUG("WorksheetView::cartesianPlotAdd()");
 	if (action == addCurveAction)
 		plot->addCurve();
 	else if (action == addHistogramAction)
 		plot->addHistogram();
 	else if (action == addEquationCurveAction)
 		plot->addEquationCurve();
 	else if (action == addDataReductionCurveAction)
 		plot->addDataReductionCurve();
 	else if (action == addDifferentiationCurveAction)
 		plot->addDifferentiationCurve();
 	else if (action == addIntegrationCurveAction)
 		plot->addIntegrationCurve();
 	else if (action == addInterpolationCurveAction)
 		plot->addInterpolationCurve();
 	else if (action == addSmoothCurveAction)
 		plot->addSmoothCurve();
 	else if (action == addFitCurveAction)
 		plot->addFitCurve();
 	else if (action == addFourierFilterCurveAction)
 		plot->addFourierFilterCurve();
 	else if (action == addFourierTransformCurveAction)
 		plot->addFourierTransformCurve();
 	else if (action == addConvolutionCurveAction)
 		plot->addConvolutionCurve();
 	else if (action == addCorrelationCurveAction)
 		plot->addCorrelationCurve();
 	else if (action == addLegendAction)
 		plot->addLegend();
 	else if (action == addHorizontalAxisAction)
 		plot->addHorizontalAxis();
 	else if (action == addVerticalAxisAction)
 		plot->addVerticalAxis();
 	else if (action == addCustomPointAction)
 		plot->addCustomPoint();
 // analysis actions
 	else if (action == addDataReductionAction)
 		plot->addDataReductionCurve();
 	else if (action == addDifferentiationAction)
 		plot->addDifferentiationCurve();
 	else if (action == addIntegrationAction)
 		plot->addIntegrationCurve();
 	else if (action == addInterpolationAction)
 		plot->addInterpolationCurve();
 	else if (action == addSmoothAction)
 		plot->addSmoothCurve();
 	else if (action == addFitAction)
 		plot->addFitCurve();
 	else if (action == addFourierFilterAction)
 		plot->addFourierFilterCurve();
 	else if (action == addFourierTransformAction)
 		plot->addFourierTransformCurve();
 	else if (action == addConvolutionAction)
 		plot->addConvolutionCurve();
 	else if (action == addCorrelationAction)
 		plot->addCorrelationCurve();
 }
 
 void WorksheetView::cartesianPlotNavigationChanged(QAction* action) {
 	CartesianPlot::NavigationOperation op = (CartesianPlot::NavigationOperation)action->data().toInt();
 	if (m_worksheet->cartesianPlotActionMode() == Worksheet::ApplyActionToSelection) {
 		for (auto* plot : m_worksheet->children<CartesianPlot>() ) {
 			if (m_selectedItems.indexOf(plot->graphicsItem()) != -1)
 				plot->navigate(op);
 		}
 	} else {
 		for (auto* plot : m_worksheet->children<CartesianPlot>() )
 			plot->navigate(op);
 	}
 }
 
 void WorksheetView::presenterMode() {
 	KConfigGroup group = KSharedConfig::openConfig()->group("Settings_Worksheet");
 
 	//show dynamic presenter widget, if enabled
 	if (group.readEntry("PresenterModeInteractive", false)) {
 		auto* dynamicPresenterWidget = new DynamicPresenterWidget(m_worksheet);
 		dynamicPresenterWidget->showFullScreen();
 		return;
 	}
 
 	//show static presenter widget (default)
 	QRectF sourceRect(scene()->sceneRect());
 
 	int w = Worksheet::convertFromSceneUnits(sourceRect.width(), Worksheet::Millimeter);
 	int h = Worksheet::convertFromSceneUnits(sourceRect.height(), Worksheet::Millimeter);
 	w *= QApplication::desktop()->physicalDpiX()/25.4;
 	h *= QApplication::desktop()->physicalDpiY()/25.4;
 
 	QRectF targetRect(0, 0, w, h);
 
 	QDesktopWidget* const dw = QApplication::desktop();
 	const int primaryScreenIdx = dw->primaryScreen();
 	const QRectF& screenSize = dw->availableGeometry(primaryScreenIdx);
 
 	if (targetRect.width() > screenSize.width() || ((targetRect.height() > screenSize.height()))) {
 		const double ratio = qMin(screenSize.width() / targetRect.width(), screenSize.height() / targetRect.height());
 		targetRect.setWidth(targetRect.width()* ratio);
 		targetRect.setHeight(targetRect.height() * ratio);
 	}
 
 	QImage image(QSize(targetRect.width(), targetRect.height()), QImage::Format_ARGB32_Premultiplied);
 	image.fill(Qt::transparent);
 	QPainter painter;
 	painter.begin(&image);
 	painter.setRenderHint(QPainter::Antialiasing);
 	exportPaint(&painter, targetRect, sourceRect, true);
 	painter.end();
 
 	PresenterWidget* presenterWidget = new PresenterWidget(QPixmap::fromImage(image), m_worksheet->name());
 	presenterWidget->showFullScreen();
 }