diff --git a/src/KGantt/kganttdatetimetimelinedialog.cpp b/src/KGantt/kganttdatetimetimelinedialog.cpp
index aeb5ea5..2f2f503 100644
--- a/src/KGantt/kganttdatetimetimelinedialog.cpp
+++ b/src/KGantt/kganttdatetimetimelinedialog.cpp
@@ -1,122 +1,122 @@
 /*
  * Copyright (C) 2020 Dag Andersen <danders@get2net.dk
  *
  * This file is part of the KGantt library.
  *
  * 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, see <https://www.gnu.org/licenses/>.
  */
 
 
 #include "kganttdatetimetimelinedialog.h"
 #include "ui_kganttdatetimetimelinedialog.h"
 #include "kganttdatetimetimeline.h"
 #include "kganttpenstylecombobox.h"
 
 #include <QPixmap>
 #include <QPainter>
 #include <QPen>
 #include <QColorDialog>
 #include <QTime>
 #include <QTimer>
 #include <QMetaEnum>
 #include <QAbstractItemModel>
 
 namespace KGantt {
     class DateTimeTimeLineDialog::Private
     {
     public:
-        Private() {}
+        Private() : timeLine(nullptr) {}
 
         Ui::DateTimeTimeLineDialog ui;
         DateTimeTimeLine *timeLine;
         QColor penColor;
     };
 }
 
 using namespace KGantt;
 
 DateTimeTimeLineDialog::DateTimeTimeLineDialog(DateTimeTimeLine *timeLine, QWidget* parent)
     : QDialog(parent)
     , d( new Private())
 {
     d->timeLine = timeLine;
     d->ui.setupUi(this);
 
     DateTimeTimeLine::Options opt = d->timeLine->options();
     if (opt & DateTimeTimeLine::Foreground) {
         d->ui.foreground->setChecked(true);
     } else if (opt & DateTimeTimeLine::Background) {
         d->ui.background->setChecked(true);
     }
-    d->ui.useCustomPen->setCheckState(opt & DateTimeTimeLine::UseCustomPen ? Qt::Checked : Qt::Unchecked);
+    d->ui.useCustomPen->setCheckState((opt & DateTimeTimeLine::UseCustomPen) ? Qt::Checked : Qt::Unchecked);
 
     QPen pen = d->timeLine->pen(); // get standard if not set
     d->ui.penWidth->setValue(pen.width());
     d->ui.penStyle->setCurrentStyle(pen.style());
     d->penColor = pen.color();
 
     d->ui.updateInterval->setTime(QTime::fromMSecsSinceStartOfDay(d->timeLine->interval()));
     d->ui.dateTime->setDateTime(timeLine->dateTime());
 
     connect(d->ui.buttonBox, &QDialogButtonBox::accepted, this, &DateTimeTimeLineDialog::ok);
     connect(d->ui.openColorDialog, &QAbstractButton::clicked, this, &DateTimeTimeLineDialog::openColorDialog);
 
     QTimer::singleShot(0, this, SLOT(updateColorButton())); // wait for correct button size
 }
 
 DateTimeTimeLineDialog::~DateTimeTimeLineDialog()
 {
 }
 
 void DateTimeTimeLineDialog::ok()
 {
     DateTimeTimeLine::Options opt;
     if (d->ui.foreground->isChecked()) {
         opt |= DateTimeTimeLine::Foreground;
     } else if (d->ui.background->isChecked()) {
         opt |= DateTimeTimeLine::Background;
     }
     if (d->ui.useCustomPen->checkState()) {
         opt |= DateTimeTimeLine::UseCustomPen;
     }
     d->timeLine->setOptions(opt);
     QPen pen;
     pen.setWidth(d->ui.penWidth->value());
     pen.setStyle(static_cast<Qt::PenStyle>(d->ui.penStyle->currentData().toInt()));
     pen.setColor(d->penColor);
     d->timeLine->setPen(pen);
 
     d->timeLine->setInterval(d->ui.updateInterval->time().msecsSinceStartOfDay());
     d->timeLine->setDateTime(d->ui.dateTime->dateTime());
 }
 
 void DateTimeTimeLineDialog::updateColorButton()
 {
     QSize size = d->ui.openColorDialog->size();
     qInfo()<<Q_FUNC_INFO<<size<<d->penColor;
     QPixmap px(size);
     px.fill();
     QPainter painter(&px);
     painter.fillRect(0, 0, size.width(), size.height(), d->penColor);
     d->ui.openColorDialog->setIcon(QIcon(px));    
 }
 
 void DateTimeTimeLineDialog::openColorDialog()
 {
     QColorDialog dlg;
     if (dlg.exec() == QDialog::Accepted) {
         d->penColor = dlg.selectedColor();
         updateColorButton();
     }
 }
diff --git a/src/KGantt/kganttpenstylecombobox.h b/src/KGantt/kganttpenstylecombobox.h
index 9b4024f..e1467d5 100644
--- a/src/KGantt/kganttpenstylecombobox.h
+++ b/src/KGantt/kganttpenstylecombobox.h
@@ -1,47 +1,47 @@
 /*
  * Copyright (C) 2020 Dag Andersen <danders@get2net.dk
  *
  * This file is part of the KGantt library.
  *
  * 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, see <https://www.gnu.org/licenses/>.
  */
 
 #ifndef KGANTTPENSTYLECOMBOBOX_H
 #define KGANTTPENSTYLECOMBOBOX_H
 
 #include <QComboBox>
 
 #include "kgantt_export.h"
 
 QT_BEGIN_NAMESPACE
 class QPaintEvent;
 QT_END_NAMESPACE
 
 namespace KGantt {
 
     class KGANTT_EXPORT PenStyleComboBox : public QComboBox
     {
         Q_OBJECT
     public:
-        PenStyleComboBox(QWidget *parent = nullptr);
+        explicit PenStyleComboBox(QWidget *parent = nullptr);
 
         void setCurrentStyle(Qt::PenStyle style);
         Qt::PenStyle currentStyle() const;
 
     protected:
         void paintEvent(QPaintEvent *pe) override;
     };
 }
 
 #endif