Improved tab bar scrolling (#678)

* Improved tab bar scrolling

* Fix: tab bar scroll for mouse

Author: Servall4

src/DockAreaTabBar.cpp

@@ -160,19 +160,9 @@ CDockAreaTabBar::~CDockAreaTabBar()
 //============================================================================
 void CDockAreaTabBar::wheelEvent(QWheelEvent* Event)
 {
-	Event->accept();
-	const int direction = Event->angleDelta().y();
-	if (direction < 0)
-	{
-		horizontalScrollBar()->setValue(horizontalScrollBar()->value() + 20);
-	}
-	else
-	{
-		horizontalScrollBar()->setValue(horizontalScrollBar()->value() - 20);
-	}
+    QCoreApplication::sendEvent(horizontalScrollBar(), Event);
 }
 
-
 //============================================================================
 void CDockAreaTabBar::setCurrentIndex(int index)
 {
@@ -356,7 +346,7 @@ void CDockAreaTabBar::onCloseOtherTabsRequested()
 				CDockWidget::DockWidgetDeleteOnClose) ? 1 : 0;
 			closeTab(i);
 
-			// If the the dock widget blocks closing, i.e. if the flag
+			// If the dock widget blocks closing, i.e. if the flag
 			// CustomCloseHandling is set, and the dock widget is still open,
 			// then we do not need to correct the index
 			if (Tab->dockWidget()->isClosed())

src/DockAreaTabBar.h

@@ -65,8 +65,7 @@ private Q_SLOTS:
 	void onTabWidgetMoved(const QPoint& GlobalPos);
 
 protected:
-	virtual void wheelEvent(QWheelEvent* Event) override;
-
+    virtual void wheelEvent(QWheelEvent* Event) override;
 
 public:
 	using Super = QScrollArea;