diff --git a/src/kdefrontend/dockwidgets/ColumnDock.cpp b/src/kdefrontend/dockwidgets/ColumnDock.cpp
index 9e3564697..b7c8e4cfa 100644
--- a/src/kdefrontend/dockwidgets/ColumnDock.cpp
+++ b/src/kdefrontend/dockwidgets/ColumnDock.cpp
@@ -1,423 +1,436 @@
 /***************************************************************************
     File                 : ColumnDock.cpp
     Project              : LabPlot
     --------------------------------------------------------------------
-    Copyright            : (C) 2011-2017 by Alexander Semke (alexander.semke@web.de)
+    Copyright            : (C) 2011-2018 by Alexander Semke (alexander.semke@web.de)
     Copyright            : (C) 2013-2017 by Stefan Gerlach (stefan.gerlach@uni.kn)
     Description          : widget for column properties
 
  ***************************************************************************/
 
 /***************************************************************************
  *                                                                         *
  *  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 "ColumnDock.h"
 
 #include "backend/core/AbstractFilter.h"
 #include "backend/core/datatypes/SimpleCopyThroughFilter.h"
 #include "backend/core/datatypes/Double2StringFilter.h"
 #include "backend/core/datatypes/String2DoubleFilter.h"
 #include "backend/core/datatypes/DateTime2StringFilter.h"
 #include "backend/core/datatypes/String2DateTimeFilter.h"
 #include "backend/datasources/LiveDataSource.h"
 #include "backend/spreadsheet/Spreadsheet.h"
 
 #include <KLocalizedString>
 
 /*!
   \class ColumnDock
   \brief Provides a widget for editing the properties of the spreadsheet columns currently selected in the project explorer.
 
   \ingroup kdefrontend
 */
 
 ColumnDock::ColumnDock(QWidget* parent) : QWidget(parent), m_column(nullptr), m_initializing(false) {
 	ui.setupUi(this);
 
 	connect(ui.leName, &QLineEdit::textChanged, this, &ColumnDock::nameChanged);
 	connect(ui.leComment, &QLineEdit::textChanged, this, &ColumnDock::commentChanged);
 	connect(ui.cbType, SIGNAL(currentIndexChanged(int)), this, SLOT(typeChanged(int)));
 	connect(ui.cbFormat, SIGNAL(currentIndexChanged(int)), this, SLOT(formatChanged(int)));
 	connect(ui.sbPrecision, SIGNAL(valueChanged(int)), this, SLOT(precisionChanged(int)) );
 	connect(ui.cbPlotDesignation, SIGNAL(currentIndexChanged(int)), this, SLOT(plotDesignationChanged(int)));
 
 	retranslateUi();
 }
 
 void ColumnDock::setColumns(QList<Column*> list) {
 	m_initializing = true;
 	m_columnsList = list;
 	m_column = list.first();
 
 	//check whether we have non-editable columns (e.g. columns for residuals calculated in XYFitCurve)
 	bool nonEditable = false;
 	for (auto* col : m_columnsList) {
 		auto* s = dynamic_cast<Spreadsheet*>(col->parentAspect());
 		if (s) {
 			if (dynamic_cast<LiveDataSource*>(s)) {
 				nonEditable = true;
 				break;
 			}
 		} else {
 			nonEditable = true;
 			break;
 		}
 	}
 
 	if (list.size() == 1) {
 		//names and comments of non-editable columns in a file data source can be changed.
 		if (!nonEditable && dynamic_cast<LiveDataSource*>(m_column->parentAspect()) != nullptr) {
 			ui.leName->setEnabled(false);
 			ui.leComment->setEnabled(false);
 		} else {
 			ui.leName->setEnabled(true);
 			ui.leComment->setEnabled(true);
 		}
 
 		ui.leName->setText(m_column->name());
 		ui.leComment->setText(m_column->comment());
 	} else {
 		ui.leName->setEnabled(false);
 		ui.leComment->setEnabled(false);
 
 		ui.leName->setText("");
 		ui.leComment->setText("");
 	}
 
 	//show the properties of the first column
 	AbstractColumn::ColumnMode columnMode = m_column->columnMode();
-	ui.cbType->setCurrentIndex(ui.cbType->findData((int)columnMode));
+	this->updateFormatWidgets(columnMode);
+	this->updateTypeWidgets(columnMode);
+	ui.cbPlotDesignation->setCurrentIndex( int(m_column->plotDesignation()) );
 
 	//disable widgets if we have at least one non-editable column
 	ui.cbType->setEnabled(!nonEditable);
 	ui.lFormat->setVisible(!nonEditable);
 	ui.cbFormat->setVisible(!nonEditable);
 	ui.lPrecision->setVisible(!nonEditable);
 	ui.sbPrecision->setVisible(!nonEditable);
 	ui.lPlotDesignation->setVisible(!nonEditable);
 	ui.cbPlotDesignation->setVisible(!nonEditable);
 	if (nonEditable) {
 		m_initializing = false;
 		return;
 	}
 
-	this->updateFormatWidgets(columnMode);
+	// slots
+	connect(m_column, &AbstractColumn::aspectDescriptionChanged, this, &ColumnDock::columnDescriptionChanged);
+	connect(m_column, &AbstractColumn::modeChanged, this, &ColumnDock::columnModeChanged);
+	connect(m_column->outputFilter(), &AbstractSimpleFilter::formatChanged, this, &ColumnDock::columnFormatChanged);
+	connect(m_column->outputFilter(), &AbstractSimpleFilter::digitsChanged, this, &ColumnDock::columnPrecisionChanged);
+	connect(m_column, &AbstractColumn::plotDesignationChanged, this, &ColumnDock::columnPlotDesignationChanged);
 
-	switch(columnMode) {
+	m_initializing = false;
+}
+
+void ColumnDock::updateTypeWidgets(AbstractColumn::ColumnMode mode) {
+	ui.cbType->setCurrentIndex(ui.cbType->findData((int)mode));
+	switch(mode) {
 	case AbstractColumn::Numeric: {
 			auto* filter = static_cast<Double2StringFilter*>(m_column->outputFilter());
 			ui.cbFormat->setCurrentIndex(ui.cbFormat->findData(filter->numericFormat()));
 			ui.sbPrecision->setValue(filter->numDigits());
 			break;
 		}
 	case AbstractColumn::Month:
 	case AbstractColumn::Day:
 	case AbstractColumn::DateTime: {
 			auto* filter = static_cast<DateTime2StringFilter*>(m_column->outputFilter());
 			DEBUG("	set column format: " << filter->format().toStdString());
 			ui.cbFormat->setCurrentIndex(ui.cbFormat->findData(filter->format()));
 			break;
 		}
 	case AbstractColumn::Integer:	// nothing to set
 	case AbstractColumn::Text:
 		break;
 	}
-
-	ui.cbPlotDesignation->setCurrentIndex( int(m_column->plotDesignation()) );
-
-	// slots
-	connect(m_column, SIGNAL(aspectDescriptionChanged(const AbstractAspect*)),this, SLOT(columnDescriptionChanged(const AbstractAspect*)));
-	connect(m_column->outputFilter(), SIGNAL(formatChanged()),this, SLOT(columnFormatChanged()));
-	connect(m_column->outputFilter(), SIGNAL(digitsChanged()),this, SLOT(columnPrecisionChanged()));
-	connect(m_column, SIGNAL(plotDesignationChanged(const AbstractColumn*)),this, SLOT(columnPlotDesignationChanged(const AbstractColumn*)));
-
-	m_initializing = false;
 }
 
 /*!
   depending on the currently selected column type (column mode) updates the widgets for the column format,
   shows/hides the allowed widgets, fills the corresponding combobox with the possible entries.
   Called when the type (column mode) is changed.
 */
-void ColumnDock::updateFormatWidgets(const AbstractColumn::ColumnMode columnMode) {
+void ColumnDock::updateFormatWidgets(AbstractColumn::ColumnMode mode) {
 	ui.cbFormat->clear();
 
-	switch (columnMode) {
+	switch (mode) {
 	case AbstractColumn::Numeric:
 		ui.cbFormat->addItem(i18n("Decimal"), QVariant('f'));
 		ui.cbFormat->addItem(i18n("Scientific (e)"), QVariant('e'));
 		ui.cbFormat->addItem(i18n("Scientific (E)"), QVariant('E'));
 		ui.cbFormat->addItem(i18n("Automatic (g)"), QVariant('g'));
 		ui.cbFormat->addItem(i18n("Automatic (G)"), QVariant('G'));
 		break;
 	case AbstractColumn::Month:
 		ui.cbFormat->addItem(i18n("Number without Leading Zero"), QVariant("M"));
 		ui.cbFormat->addItem(i18n("Number with Leading Zero"), QVariant("MM"));
 		ui.cbFormat->addItem(i18n("Abbreviated Month Name"), QVariant("MMM"));
 		ui.cbFormat->addItem(i18n("Full Month Name"), QVariant("MMMM"));
 		break;
 	case AbstractColumn::Day:
 		ui.cbFormat->addItem(i18n("Number without Leading Zero"), QVariant("d"));
 		ui.cbFormat->addItem(i18n("Number with Leading Zero"), QVariant("dd"));
 		ui.cbFormat->addItem(i18n("Abbreviated Day Name"), QVariant("ddd"));
 		ui.cbFormat->addItem(i18n("Full Day Name"), QVariant("dddd"));
 		break;
 	case AbstractColumn::DateTime:
 		for (const auto& s : AbstractColumn::dateTimeFormats())
 			ui.cbFormat->addItem(s, QVariant(s));
 		break;
 	case AbstractColumn::Integer:
 	case AbstractColumn::Text:
 		break;
 	}
 
-	if (columnMode == AbstractColumn::Numeric) {
+	if (mode == AbstractColumn::Numeric) {
 		ui.lPrecision->show();
 		ui.sbPrecision->show();
 	} else {
 		ui.lPrecision->hide();
 		ui.sbPrecision->hide();
 	}
 
-	if (columnMode == AbstractColumn::Text || columnMode == AbstractColumn::Integer) {
+	if (mode == AbstractColumn::Text || mode == AbstractColumn::Integer) {
 		ui.lFormat->hide();
 		ui.cbFormat->hide();
 	} else {
 		ui.lFormat->show();
 		ui.cbFormat->show();
 	}
 
-	if (columnMode == AbstractColumn::DateTime) {
+	if (mode == AbstractColumn::DateTime) {
 		ui.cbFormat->setEditable(true);
 		ui.cbFormat->setCurrentItem("yyyy-MM-dd hh:mm:ss.zzz");
 	} else {
 		ui.cbFormat->setEditable(false);
 		ui.cbFormat->setCurrentIndex(0);
 	}
 }
 
 //*************************************************************
 //******** SLOTs for changes triggered in ColumnDock **********
 //*************************************************************
 void ColumnDock::retranslateUi() {
 	m_initializing = true;
 
 	ui.cbType->clear();
 	ui.cbType->addItem(i18n("Numeric"), QVariant(int(AbstractColumn::Numeric)));
 	ui.cbType->addItem(i18n("Integer"), QVariant(int(AbstractColumn::Integer)));
 	ui.cbType->addItem(i18n("Text"), QVariant(int(AbstractColumn::Text)));
 	ui.cbType->addItem(i18n("Month Names"), QVariant(int(AbstractColumn::Month)));
 	ui.cbType->addItem(i18n("Day Names"), QVariant(int(AbstractColumn::Day)));
 	ui.cbType->addItem(i18n("Date and Time"), QVariant(int(AbstractColumn::DateTime)));
 
 	ui.cbPlotDesignation->clear();
 	ui.cbPlotDesignation->addItem(i18n("None"));
 	ui.cbPlotDesignation->addItem(i18n("X"));
 	ui.cbPlotDesignation->addItem(i18n("Y"));
 	ui.cbPlotDesignation->addItem(i18n("Z"));
 	ui.cbPlotDesignation->addItem(i18n("X-error"));
 	ui.cbPlotDesignation->addItem(i18n("X-error -"));
 	ui.cbPlotDesignation->addItem(i18n("X-error +"));
 	ui.cbPlotDesignation->addItem(i18n("Y-error"));
 	ui.cbPlotDesignation->addItem(i18n("Y-error -"));
 	ui.cbPlotDesignation->addItem(i18n("Y-error +"));
 
 	m_initializing = false;
 }
 
 void ColumnDock::nameChanged() {
 	if (m_initializing)
 		return;
 
 	m_columnsList.first()->setName(ui.leName->text());
 }
 
 void ColumnDock::commentChanged() {
 	if (m_initializing)
 		return;
 
 	m_columnsList.first()->setComment(ui.leComment->text());
 }
 
 /*!
   called when the type (column mode - numeric, text etc.) of the column was changed.
 */
 void ColumnDock::typeChanged(int index) {
 	DEBUG("ColumnDock::typeChanged()");
 	if (m_initializing)
 		return;
 
 	AbstractColumn::ColumnMode columnMode = (AbstractColumn::ColumnMode)ui.cbType->itemData(index).toInt();
 	int format_index = ui.cbFormat->currentIndex();
 
 	m_initializing = true;
 	this->updateFormatWidgets(columnMode);
 	m_initializing = false;
 
 	switch(columnMode) {
 	case AbstractColumn::Numeric: {
 			int digits = ui.sbPrecision->value();
 			for (auto* col : m_columnsList) {
 				col->beginMacro(i18n("%1: change column type", col->name()));
 				col->setColumnMode(columnMode);
 				auto* filter = static_cast<Double2StringFilter*>(col->outputFilter());
 				filter->setNumericFormat(ui.cbFormat->itemData(format_index).toChar().toLatin1());
 				filter->setNumDigits(digits);
 				col->endMacro();
 			}
 			break;
 		}
 	case AbstractColumn::Integer:
 	case AbstractColumn::Text:
 		for (auto* col : m_columnsList)
 			col->setColumnMode(columnMode);
 		break;
 	case AbstractColumn::Month:
 	case AbstractColumn::Day:
 		for (auto* col : m_columnsList) {
 			col->beginMacro(i18n("%1: change column type", col->name()));
 			// the format is saved as item data
 			QString format = ui.cbFormat->itemData(ui.cbFormat->currentIndex()).toString();
 			col->setColumnMode(columnMode);
 			auto* filter = static_cast<DateTime2StringFilter*>(col->outputFilter());
 			filter->setFormat(format);
 			col->endMacro();
 		}
 		break;
 	case AbstractColumn::DateTime:
 		for (auto* col : m_columnsList) {
 			col->beginMacro(i18n("%1: change column type", col->name()));
 			// the format is the current text
 			QString format = ui.cbFormat->currentText();
 			col->setColumnMode(columnMode);
 			auto* filter = static_cast<DateTime2StringFilter*>(col->outputFilter());
 			filter->setFormat(format);
 			col->endMacro();
 		}
 		break;
 	}
 	DEBUG("ColumnDock::typeChanged() DONE");
 }
 
 /*!
   called when the format for the current type (column mode) was changed.
 */
 void ColumnDock::formatChanged(int index) {
 	DEBUG("ColumnDock::formatChanged()");
 	if (m_initializing)
 		return;
 
 	AbstractColumn::ColumnMode mode = (AbstractColumn::ColumnMode)ui.cbType->itemData(ui.cbType->currentIndex()).toInt();
 	int format_index = index;
 
 	switch(mode) {
 	case AbstractColumn::Numeric: {
 			for (auto* col : m_columnsList) {
 				auto* filter = static_cast<Double2StringFilter*>(col->outputFilter());
 				filter->setNumericFormat(ui.cbFormat->itemData(format_index).toChar().toLatin1());
 			}
 			break;
 		}
 	case AbstractColumn::Integer:
 	case AbstractColumn::Text:
 		break;
 	case AbstractColumn::Month:
 	case AbstractColumn::Day:
 	case AbstractColumn::DateTime: {
 			QString format = ui.cbFormat->itemData(ui.cbFormat->currentIndex()).toString();
 			for (auto* col : m_columnsList) {
 				auto* filter = static_cast<DateTime2StringFilter*>(col->outputFilter());
 				filter->setFormat(format);
 			}
 			break;
 		}
 	}
 	DEBUG("ColumnDock::formatChanged() DONE");
 }
 
 void ColumnDock::precisionChanged(int digits) {
 	if (m_initializing)
 		return;
 
 	for (auto* col : m_columnsList) {
 		auto* filter = static_cast<Double2StringFilter*>(col->outputFilter());
 		filter->setNumDigits(digits);
 	}
 }
 
 void ColumnDock::plotDesignationChanged(int index) {
 	if (m_initializing)
 		return;
 
 	auto pd = AbstractColumn::PlotDesignation(index);
 	for (auto* col : m_columnsList)
 		col->setPlotDesignation(pd);
 }
 
 //*************************************************************
 //********* SLOTs for changes triggered in Column *************
 //*************************************************************
 void ColumnDock::columnDescriptionChanged(const AbstractAspect* aspect) {
 	if (m_column != aspect)
 		return;
 
 	m_initializing = true;
 	if (aspect->name() != ui.leName->text())
 		ui.leName->setText(aspect->name());
 	else if (aspect->comment() != ui.leComment->text())
 		ui.leComment->setText(aspect->comment());
 	m_initializing = false;
 }
 
+void ColumnDock::columnModeChanged(const AbstractAspect* aspect) {
+	if (m_column != aspect)
+		return;
+
+	m_initializing = true;
+	AbstractColumn::ColumnMode columnMode = m_column->columnMode();
+	this->updateFormatWidgets(columnMode);
+	this->updateTypeWidgets(columnMode);
+	m_initializing = false;
+}
+
 void ColumnDock::columnFormatChanged() {
 	DEBUG("ColumnDock::columnFormatChanged()");
 	m_initializing = true;
 	AbstractColumn::ColumnMode columnMode = m_column->columnMode();
 	switch(columnMode) {
 	case AbstractColumn::Numeric: {
 			auto* filter = static_cast<Double2StringFilter*>(m_column->outputFilter());
 			ui.cbFormat->setCurrentIndex(ui.cbFormat->findData(filter->numericFormat()));
 			break;
 		}
 	case AbstractColumn::Integer:
 	case AbstractColumn::Text:
 		break;
 	case AbstractColumn::Month:
 	case AbstractColumn::Day:
 	case AbstractColumn::DateTime: {
 			auto* filter = static_cast<DateTime2StringFilter*>(m_column->outputFilter());
 			ui.cbFormat->setCurrentIndex(ui.cbFormat->findData(filter->format()));
 			break;
 		}
 	}
 	m_initializing = false;
 }
 
 void ColumnDock::columnPrecisionChanged() {
 	m_initializing = true;
 	auto* filter = static_cast<Double2StringFilter*>(m_column->outputFilter());
 	ui.sbPrecision->setValue(filter->numDigits());
 	m_initializing = false;
 }
 
 void ColumnDock::columnPlotDesignationChanged(const AbstractColumn* col) {
 	m_initializing = true;
 	ui.cbPlotDesignation->setCurrentIndex( int(col->plotDesignation()) );
 	m_initializing = false;
 }
diff --git a/src/kdefrontend/dockwidgets/ColumnDock.h b/src/kdefrontend/dockwidgets/ColumnDock.h
index 00990bc57..dc0fa13e0 100644
--- a/src/kdefrontend/dockwidgets/ColumnDock.h
+++ b/src/kdefrontend/dockwidgets/ColumnDock.h
@@ -1,73 +1,75 @@
 /***************************************************************************
     File                 : ColumnDock.h
     Project              : LabPlot
     Description          : widget for column properties
     --------------------------------------------------------------------
-    Copyright            : (C) 2011 Alexander Semke (alexander.semke@web.de)
+    Copyright            : (C) 2011-2018 Alexander Semke (alexander.semke@web.de)
     Copyright            : (C) 2017 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                                           *
  *                                                                         *
  ***************************************************************************/
 
 #ifndef COLUMNDOCK_H
 #define COLUMNDOCK_H
 
 #include "backend/core/column/Column.h"
 #include "ui_columndock.h"
 
 template <class T> class QList;
 
 class ColumnDock : public QWidget {
 	Q_OBJECT
 
 public:
 	explicit ColumnDock(QWidget*);
 	void setColumns(QList<Column*>);
 
 private:
 	Ui::ColumnDock ui;
 	QList<Column*> m_columnsList;
 	Column* m_column;
 	bool m_initializing;
 
-	void updateFormatWidgets(const AbstractColumn::ColumnMode);
+	void updateTypeWidgets(AbstractColumn::ColumnMode);
+	void updateFormatWidgets(AbstractColumn::ColumnMode);
 
 private slots:
 	void retranslateUi();
 
 	void nameChanged();
 	void commentChanged();
 	void typeChanged(int);
 	void formatChanged(int);
 	void precisionChanged(int);
 	void plotDesignationChanged(int);
 
 	//SLOTs for changes triggered in Column
 	void columnDescriptionChanged(const AbstractAspect*);
+	void columnModeChanged(const AbstractAspect*);
 	void columnFormatChanged();
 	void columnPrecisionChanged();
 	void columnPlotDesignationChanged(const AbstractColumn*);
 
 signals:
 	void info(const QString&);
 };
 
 #endif // COLUMNDOCK_H