Fix 2 crashes in singleShot timers while undocking tabs (especially in auto hide mode)

Author: Marcus Venturi

src/DockAreaTabBar.cpp

@@ -37,6 +37,7 @@
 #include <QApplication>
 #include <QtGlobal>
 #include <QTimer>
+#include <QPointer>
 
 #include "FloatingDockContainer.h"
 #include "DockAreaWidget.h"
@@ -111,9 +112,15 @@ void DockAreaTabBarPrivate::updateTabs()
 			// Sometimes the synchronous calculation of the rectangular area fails
 			// Therefore we use QTimer::singleShot here to execute the call
 			// within the event loop - see #520
-			QTimer::singleShot(0, _this, [&, TabWidget]
+			QPointer<CDockAreaTabBar> __this = _this;
+			QPointer<CDockWidgetTab> __tabWidget = TabWidget;
+
+			QTimer::singleShot(0, TabWidget, [__this, __tabWidget]
 			{
-				_this->ensureWidgetVisible(TabWidget);
+				if (__this && __tabWidget)
+				{
+					__this->ensureWidgetVisible(__tabWidget);				
+				}
 			});
 		}
 		else

src/DockContainerWidget.cpp

@@ -151,7 +151,7 @@ class DockContainerWidgetPrivate
 	int VisibleDockAreaCount = -1;
 	CDockAreaWidget* TopLevelDockArea = nullptr;
 	QTimer DelayedAutoHideTimer;
-	CAutoHideTab* DelayedAutoHideTab;
+	QPointer<CAutoHideTab> DelayedAutoHideTab;
 	bool DelayedAutoHideShow = false;
 
 	/**
@@ -396,10 +396,12 @@ DockContainerWidgetPrivate::DockContainerWidgetPrivate(CDockContainerWidget* _pu
 	std::fill(std::begin(LastAddedAreaCache),std::end(LastAddedAreaCache), nullptr);
 	DelayedAutoHideTimer.setSingleShot(true);
 	DelayedAutoHideTimer.setInterval(500);
-	QObject::connect(&DelayedAutoHideTimer, &QTimer::timeout, [this](){
-		auto GlobalPos = DelayedAutoHideTab->mapToGlobal(QPoint(0, 0));
-		qApp->sendEvent(DelayedAutoHideTab, new QMouseEvent(QEvent::MouseButtonPress,
+	QObject::connect(&DelayedAutoHideTimer, &QTimer::timeout, [this](){		
+		if (DelayedAutoHideTab) {
+			auto GlobalPos = DelayedAutoHideTab->mapToGlobal(QPoint(0, 0));
+			qApp->sendEvent(DelayedAutoHideTab, new QMouseEvent(QEvent::MouseButtonPress,
 				QPoint(0, 0), GlobalPos, Qt::LeftButton, {Qt::LeftButton}, Qt::NoModifier));
+		}
 	});
 }