Implemented initial support for dragging auto hide tabs

src/AutoHideTab.cpp

@@ -39,6 +39,8 @@
 #include "DockAreaWidget.h"
 #include "DockManager.h"
 #include "DockWidget.h"
+#include "FloatingDragPreview.h"
+#include "DockOverlay.h"
 
 namespace ads
 {
@@ -54,6 +56,11 @@ struct AutoHideTabPrivate
     CAutoHideSideBar* SideBar = nullptr;
 	Qt::Orientation Orientation{Qt::Vertical};
 	QElapsedTimer TimeSinceHoverMousePress;
+	bool MousePressed = false;
+	eDragState DragState = DraggingInactive;
+	QPoint GlobalDragStartMousePosition;
+	QPoint DragStartMousePosition;
+	IFloatingWidget* FloatingWidget = nullptr;
 
 	/**
 	 * Private data constructor
@@ -99,6 +106,41 @@ struct AutoHideTabPrivate
 		Action->setEnabled(Location != _this->sideBarLocation());
 		return Action;
 	}
+
+	/**
+	 * Test function for current drag state
+	 */
+	bool isDraggingState(eDragState dragState) const
+	{
+		return this->DragState == dragState;
+	}
+
+	/**
+	 * Saves the drag start position in global and local coordinates
+	 */
+	void saveDragStartMousePosition(const QPoint& GlobalPos)
+	{
+		GlobalDragStartMousePosition = GlobalPos;
+		DragStartMousePosition = _this->mapFromGlobal(GlobalPos);
+	}
+
+	/**
+	 * Starts floating of the dock widget that belongs to this title bar
+	 * Returns true, if floating has been started and false if floating
+	 * is not possible for any reason
+	 */
+	bool startFloating(eDragState DraggingState = DraggingFloatingWidget);
+
+	template <typename T>
+	IFloatingWidget* createFloatingWidget(T* Widget)
+	{
+		auto w = new CFloatingDragPreview(Widget);
+		_this->connect(w, &CFloatingDragPreview::draggingCanceled, [=]()
+		{
+			DragState = DraggingInactive;
+		});
+		return w;
+	}
 }; // struct DockWidgetTabPrivate
 
 
@@ -127,6 +169,52 @@ void AutoHideTabPrivate::updateOrientation()
 }
 
 
+//============================================================================
+bool AutoHideTabPrivate::startFloating(eDragState DraggingState)
+{
+	auto DockArea = DockWidget->dockAreaWidget();
+    ADS_PRINT("isFloating " << dockContainer->isFloating());
+
+    ADS_PRINT("startFloating");
+	DragState = DraggingState;
+	IFloatingWidget* FloatingWidget = nullptr;
+	FloatingWidget = createFloatingWidget(DockArea);
+	auto Size = DockArea->size();
+	auto StartPos = DragStartMousePosition;
+	auto AutoHideContainer = DockWidget->autoHideDockContainer();
+	switch (SideBar->sideBarLocation())
+	{
+	case SideBarLeft:
+		 StartPos.rx() = AutoHideContainer->rect().left() + 10;
+		 break;
+
+	case SideBarRight:
+		 StartPos.rx() = AutoHideContainer->rect().right() - 10;
+		 break;
+
+	case SideBarTop:
+		 StartPos.ry() = AutoHideContainer->rect().top() + 10;
+		 break;
+
+	case SideBarBottom:
+		 StartPos.ry() = AutoHideContainer->rect().bottom() - 10;
+		 break;
+
+	case SideBarNone:
+		 return false;
+	}
+	FloatingWidget->startFloating(StartPos, Size, DraggingFloatingWidget, _this);
+	auto DockManager = DockWidget->dockManager();
+	auto Overlay = DockManager->containerOverlay();
+	Overlay->setAllowedAreas(OuterDockAreas);
+	this->FloatingWidget = FloatingWidget;
+	qApp->postEvent(DockWidget, new QEvent((QEvent::Type)internal::DockedWidgetDragStartEvent));
+
+	return true;
+}
+
+
+
 //============================================================================
 void CAutoHideTab::setSideBar(CAutoHideSideBar* SideTabBar)
 {
@@ -267,22 +355,6 @@ bool CAutoHideTab::event(QEvent* event)
 		 d->forwardEventToDockContainer(event);
 		 break;
 
-	case QEvent::MouseButtonPress:
-		 // If AutoHideShowOnMouseOver is active, then the showing is triggered
-		 // by a MousePressEvent sent to this tab. To prevent accidental hiding
-		 // of the tab by a mouse click, we wait at least 500 ms before we accept
-		 // the mouse click
-		 if (!event->spontaneous())
-		 {
-			 d->TimeSinceHoverMousePress.restart();
-			 d->forwardEventToDockContainer(event);
-		 }
-		 else if (d->TimeSinceHoverMousePress.hasExpired(500))
-		 {
-			 d->forwardEventToDockContainer(event);
-		 }
-		 break;
-
 	default:
 		break;
 	}
@@ -360,4 +432,139 @@ void CAutoHideTab::onAutoHideToActionClicked()
 }
 
 
+//============================================================================
+void CAutoHideTab::mousePressEvent(QMouseEvent* ev)
+{
+	 // If AutoHideShowOnMouseOver is active, then the showing is triggered
+	 // by a MousePressEvent sent to this tab. To prevent accidental hiding
+	 // of the tab by a mouse click, we wait at least 500 ms before we accept
+	 // the mouse click
+	 if (!ev->spontaneous())
+	 {
+		 d->TimeSinceHoverMousePress.restart();
+		 d->forwardEventToDockContainer(ev);
+	 }
+	 else if (d->TimeSinceHoverMousePress.hasExpired(500))
+	 {
+		 d->forwardEventToDockContainer(ev);
+	 }
+
+	if (ev->button() == Qt::LeftButton)
+	{
+		ev->accept();
+		d->MousePressed = true;
+        d->saveDragStartMousePosition(internal::globalPositionOf(ev));
+        d->DragState = DraggingMousePressed;
+	}
+	Super::mousePressEvent(ev);
+}
+
+
+
+//============================================================================
+void CAutoHideTab::mouseReleaseEvent(QMouseEvent* ev)
+{
+	if (ev->button() == Qt::LeftButton)
+	{
+		d->MousePressed = false;
+		auto CurrentDragState = d->DragState;
+		d->GlobalDragStartMousePosition = QPoint();
+		d->DragStartMousePosition = QPoint();
+		d->DragState = DraggingInactive;
+
+		switch (CurrentDragState)
+		{
+		case DraggingTab:
+			// End of tab moving, emit signal
+			/*if (d->DockArea)
+			{
+				ev->accept();
+                Q_EMIT moved(internal::globalPositionOf(ev));
+			}*/
+			break;
+
+		case DraggingFloatingWidget:
+			 ev->accept();
+			 d->FloatingWidget->finishDragging();
+			 break;
+
+		default:
+			/*if (CDockManager::testConfigFlag(CDockManager::FocusHighlighting))
+			{
+				d->focusController()->setDockWidgetTabPressed(false);
+			}*/
+			break; // do nothing
+		}
+	}
+
+	Super::mouseReleaseEvent(ev);
+}
+
+
+//============================================================================
+void CAutoHideTab::mouseMoveEvent(QMouseEvent* ev)
+{
+	std::cout << "CAutoHideTab::mouseMoveEvent" << std::endl;
+    if (!(ev->buttons() & Qt::LeftButton) || d->isDraggingState(DraggingInactive))
+    {
+    	d->DragState = DraggingInactive;
+        Super::mouseMoveEvent(ev);
+        return;
+    }
+
+    // move floating window
+    if (d->isDraggingState(DraggingFloatingWidget))
+    {
+        d->FloatingWidget->moveFloating();
+        Super::mouseMoveEvent(ev);
+        return;
+    }
+
+    // move tab
+    if (d->isDraggingState(DraggingTab))
+    {
+        // Moving the tab is always allowed because it does not mean moving the
+    	// dock widget around
+    	//d->moveTab(ev);
+    }
+
+    auto MappedPos = mapToParent(ev->pos());
+    bool MouseOutsideBar = (MappedPos.x() < 0) || (MappedPos.x() > parentWidget()->rect().right());
+    // Maybe a fixed drag distance is better here ?
+    int DragDistanceY = qAbs(d->GlobalDragStartMousePosition.y() - internal::globalPositionOf(ev).y());
+    std::cout << "DragDistanceY " << DragDistanceY << "  MouseOutsideBar " << MouseOutsideBar << std::endl;
+    if (DragDistanceY >= CDockManager::startDragDistance() || MouseOutsideBar)
+	{
+    	// Floating is only allowed for widgets that are floatable
+		// We can create the drag preview if the widget is movable.
+		auto Features = d->DockWidget->features();
+        if (Features.testFlag(CDockWidget::DockWidgetFloatable) || (Features.testFlag(CDockWidget::DockWidgetMovable)))
+        {
+        	// If we undock, we need to restore the initial position of this
+        	// tab because it looks strange if it remains on its dragged position
+        	/*if (d->isDraggingState(DraggingTab))
+			{
+        		parentWidget()->layout()->update();
+			}*/
+            d->startFloating();
+        }
+    	return;
+	}
+    /*else if (d->DockArea->openDockWidgetsCount() > 1
+     && (internal::globalPositionOf(ev) - d->GlobalDragStartMousePosition).manhattanLength() >= QApplication::startDragDistance()) // Wait a few pixels before start moving
+	{
+    	// If we start dragging the tab, we save its inital position to
+    	// restore it later
+    	if (DraggingTab != d->DragState)
+    	{
+    		d->TabDragStartPosition = this->pos();
+    	}
+        d->DragState = DraggingTab;
+		return;
+	}*/
+
+   Super::mouseMoveEvent(ev);
+}
+
+
 }

src/AutoHideTab.h

@@ -73,6 +73,9 @@ protected:
 	void removeFromSideBar();
 	virtual bool event(QEvent* event) override;
 	virtual void contextMenuEvent(QContextMenuEvent* ev) override;
+	virtual void mousePressEvent(QMouseEvent* ev) override;
+	virtual void mouseReleaseEvent(QMouseEvent* ev) override;
+	virtual void mouseMoveEvent(QMouseEvent* ev) override;
 
 public:
     using Super = CPushButton;

src/DockManager.h

@@ -55,6 +55,8 @@ class CIconProvider;
 class CDockComponentsFactory;
 class CDockFocusController;
 class CAutoHideSideBar;
+class CAutoHideTab;
+struct AutoHideTabPrivate;
 
 /**
  * The central dock manager that maintains the complete docking system.
@@ -87,6 +89,8 @@ private:
 	friend class CDockAreaTitleBar;
 	friend class CAutoHideDockContainer;
 	friend CAutoHideSideBar;
+	friend CAutoHideTab;
+	friend AutoHideTabPrivate;
 
 public Q_SLOTS:
 	/**