Drag and droping a window with a scroll area no longer causes an exception because scroll area children didn't have their parent switched

Drag'n'drop operation now properly ends once mouse is released

BansheeEngine/Include/BsGUIScrollArea.h

@@ -74,5 +74,7 @@ namespace BansheeEngine
 		void horzScrollUpdate(float pct);
 		void _updateLayoutInternal(CM::INT32 x, CM::INT32 y, CM::UINT32 width, CM::UINT32 height,
 			CM::Rect clipRect, CM::UINT8 widgetDepth, CM::UINT16 areaDepth);
+
+		virtual void _changeParentWidget(GUIWidget* widget);
 	};
 }

BansheeEngine/Source/BsDragAndDropManager.cpp

@@ -23,5 +23,10 @@ namespace BansheeEngine
 	{
 		if(mDropCallback != nullptr)
 			mDropCallback(processed);
+
+		mDragTypeId = 0;
+		mData = nullptr;
+		mDropCallback = nullptr;
+		mIsDragInProgress = false;
 	}
 }

BansheeEngine/Source/BsGUIScrollArea.cpp

@@ -246,6 +246,19 @@ namespace BansheeEngine
 		return false;
 	}
 
+	void GUIScrollArea::_changeParentWidget(GUIWidget* widget)
+	{
+		GUIElement::_changeParentWidget(widget);
+
+		// These two elements are not part of a layout so I need to make sure to
+		// update them manually
+		if(mVertScroll != nullptr)
+			mVertScroll->_changeParentWidget(widget);
+
+		if(mHorzScroll != nullptr)
+			mHorzScroll->_changeParentWidget(widget);
+	}
+
 	GUIScrollArea* GUIScrollArea::create(GUIWidget& parent, const GUIElementStyle* style)
 	{
 		if(style == nullptr)

CamelotClient/Source/BsEditorWidgetContainer.cpp

@@ -187,7 +187,7 @@ namespace BansheeEditor
 
 	void EditorWidgetContainer::tabDroppedCallback(bool wasDragProcessed)
 	{
-		if(!wasDragProcessed)
+		if(!wasDragProcessed && DragAndDropManager::instance().getDragTypeId() == (UINT32)DragAndDropType::EditorWidget)
 		{
 			EditorWindow* newWindow = EditorWindow::create();