add maximize button to FloatingWidgetTitleBar

src/FloatingDockContainer.cpp

@@ -44,6 +44,7 @@
 #include "DockOverlay.h"
 
 #ifdef Q_OS_LINUX
+#include <QScreen>
 #include "linux/FloatingWidgetTitleBar.h"
 #include <xcb/xcb.h>
 #endif
@@ -67,6 +68,7 @@ struct FloatingDockContainerPrivate
 #ifdef Q_OS_LINUX
     QWidget* MouseEventHandler = nullptr;
     CFloatingWidgetTitleBar* TitleBar = nullptr;
+    QRect LastGeometry;
 #endif
 
 	/**
@@ -248,7 +250,10 @@ CFloatingDockContainer::CFloatingDockContainer(CDockManager *DockManager) :
     QDockWidget::setFloating(true);
     QDockWidget::setFeatures(QDockWidget::AllDockWidgetFeatures);
     setTitleBarWidget(d->TitleBar);
+    d->LastGeometry = geometry();
     connect(d->TitleBar, SIGNAL(closeRequested()), SLOT(close()));
+    connect(d->TitleBar, &CFloatingWidgetTitleBar::maximizeRequested,
+            this, &CFloatingDockContainer::onMaximizeRequest);
 #else
 	setWindowFlags(
 	    Qt::Window | Qt::WindowMaximizeButtonHint | Qt::WindowCloseButtonHint);
@@ -623,6 +628,51 @@ void CFloatingDockContainer::finishDragging()
 #endif
 }
 
+#ifdef Q_OS_LINUX
+void CFloatingDockContainer::onMaximizeRequest()
+{
+    ADS_PRINT("CFloatingDockContainer::onMaximizeRequest()");
+    QRect screenRect;
+    QRect widgetRect;
+    const QScreen *currentScreen = nullptr;
+    int maxArea = 0;
+    // get current screen
+    for (const auto &screen : QGuiApplication::screens())
+    {
+        screenRect = screen->geometry();
+        widgetRect = this->geometry();
+        auto minX = qMax(screenRect.left(), widgetRect.left());
+        auto minY = qMax(screenRect.top(), widgetRect.top());
+        auto maxX = qMin(screenRect.right(), widgetRect.right());
+        auto maxY = qMin(screenRect.bottom(), widgetRect.bottom());
+        auto area = minX < maxX && minY < maxY ? (maxX - minX) * (maxY * minY) : 0;
+        if (area > maxArea)
+        {
+            maxArea = area;
+            currentScreen = screen;
+        }
+    }
+    if (!currentScreen)
+    {
+        return;
+    }
+    ADS_PRINT("CFloatingDockContainer::onMaximizeRequest() current screen: " + currentScreen->name());
+    // get current windows state, if it is maximized and moved or not
+    if (geometry().size() == currentScreen->availableGeometry().size())
+    {
+        setGeometry(d->LastGeometry);
+        d->TitleBar->setMaximizedIcon(false);
+    }
+    else
+    {
+        d->LastGeometry = geometry();
+        setGeometry(currentScreen->availableGeometry());
+        d->TitleBar->setMaximizedIcon(true);
+    }
+}
+#endif
+
+
 } // namespace ads
 
 //---------------------------------------------------------------------------

src/FloatingDockContainer.h

@@ -201,6 +201,15 @@ public:
      * function of the internal container widget.
      */
     QList<CDockWidget*> dockWidgets() const;
+
+#ifdef Q_OS_LINUX
+    /**
+     * This is a function respond to FloatingWidgetTitleBar::maximizeRequest()
+     * maximize or normalize the container size.
+     */
+    void onMaximizeRequest();
+#endif
+
 }; // class FloatingDockContainer
 }
  // namespace ads

src/linux/FloatingWidgetTitleBar.cpp

@@ -46,6 +46,7 @@ namespace ads
 
 using tTabLabel = CElidingLabel;
 using tCloseButton = QPushButton;
+using tMaximizeButton  = QPushButton;
 
 /**
  * @brief Private data class of public interface CFloatingWidgetTitleBar
@@ -56,6 +57,7 @@ struct FloatingWidgetTitleBarPrivate
 	QLabel *IconLabel = nullptr;
 	tTabLabel *TitleLabel;
 	tCloseButton *CloseButton = nullptr;
+    tMaximizeButton* MaximizeButton = nullptr;
 	CFloatingDockContainer *FloatingWidget = nullptr;
 	eDragState DragState = DraggingInactive;
 
@@ -82,6 +84,9 @@ void FloatingWidgetTitleBarPrivate::createLayout()
 	CloseButton = new tCloseButton();
 	CloseButton->setObjectName("floatingTitleCloseButton");
 	CloseButton->setFlat(true);
+    MaximizeButton = new tMaximizeButton();
+    MaximizeButton->setObjectName("floatingTitleMaximizeButton");
+    MaximizeButton->setFlat(true);
 
 	// The standard icons do does not look good on high DPI screens
 	QIcon CloseIcon;
@@ -97,6 +102,12 @@ void FloatingWidgetTitleBarPrivate::createLayout()
 	CloseButton->setFocusPolicy(Qt::NoFocus);
 	_this->connect(CloseButton, SIGNAL(clicked()), SIGNAL(closeRequested()));
 
+    _this->setMaximizedIcon(false);
+    MaximizeButton->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
+    MaximizeButton->setVisible(true);
+    MaximizeButton->setFocusPolicy(Qt::NoFocus);
+    _this->connect(MaximizeButton, &QPushButton::clicked, _this, &CFloatingWidgetTitleBar::maximizeRequested);
+
 	QFontMetrics fm(TitleLabel->font());
 	int Spacing = qRound(fm.height() / 4.0);
 
@@ -107,6 +118,7 @@ void FloatingWidgetTitleBarPrivate::createLayout()
 	_this->setLayout(Layout);
 	Layout->addWidget(TitleLabel, 1);
 	Layout->addSpacing(Spacing);
+    Layout->addWidget(MaximizeButton);
 	Layout->addWidget(CloseButton);
 	Layout->setAlignment(Qt::AlignCenter);
 
@@ -180,4 +192,38 @@ void CFloatingWidgetTitleBar::setTitle(const QString &Text)
 	d->TitleLabel->setText(Text);
 }
 
+void CFloatingWidgetTitleBar::mouseDoubleClickEvent(QMouseEvent *event)
+{
+    if (event->buttons() & Qt::LeftButton)
+    {
+        emit maximizeRequested();
+        event->accept();
+    }
+    else
+    {
+        QWidget::mouseDoubleClickEvent(event);
+    }
+}
+
+void CFloatingWidgetTitleBar::setMaximizedIcon(bool maximized)
+{
+    if (maximized)
+    {
+        QIcon normalIcon;
+        auto normalPixmap = this->style()->standardPixmap(QStyle::SP_TitleBarNormalButton, 0, d->MaximizeButton);
+        normalIcon.addPixmap(normalPixmap, QIcon::Normal);
+        normalIcon.addPixmap(internal::createTransparentPixmap(normalPixmap, 0.25), QIcon::Disabled);
+        d->MaximizeButton->setIcon(normalIcon);
+    }
+    else
+    {
+        QIcon MaxIcon;
+        auto maxPixmap = this->style()->standardPixmap(QStyle::SP_TitleBarMaxButton, 0, d->MaximizeButton);
+        MaxIcon.addPixmap(maxPixmap, QIcon::Normal);
+        MaxIcon.addPixmap(internal::createTransparentPixmap(maxPixmap, 0.25), QIcon::Disabled);
+        d->MaximizeButton->setIcon(MaxIcon);
+    }
+}
+
+
 } // namespace ads

src/linux/FloatingWidgetTitleBar.h

@@ -55,6 +55,7 @@ protected:
 	virtual void mousePressEvent(QMouseEvent *ev) override;
 	virtual void mouseReleaseEvent(QMouseEvent *ev) override;
 	virtual void mouseMoveEvent(QMouseEvent *ev) override;
+    virtual void mouseDoubleClickEvent(QMouseEvent *event) override;
 
 public:
 	using Super = QWidget;
@@ -75,11 +76,22 @@ public:
 	 */
 	void setTitle(const QString &Text);
 
+	/**
+	 * Change the maximize button icon according to current windows state
+	 */
+    void setMaximizedIcon(bool maximized);
+
+
 signals:
 	/**
 	 * This signal is emitted, if the close button is clicked.
 	 */
 	void closeRequested();
+
+    /**
+    * This signal is emitted, if the maximize button is clicked.
+    */
+    void maximizeRequested();
 };
 } // namespace ads
 #endif // FLOATINGWIDGETTITLEBAR_H