Fix getViewObject inheritance across all ViewProviders

src/Mod/TechDraw/Gui/ViewProviderProjGroup.cpp

@@ -32,8 +32,6 @@
 /// Here the FreeCAD includes sorted by Base,App,Gui......
 #include <Base/Console.h>
 #include <Base/Parameter.h>
-#include <Base/Exception.h>
-#include <Base/Sequencer.h>
 
 #include <App/Application.h>
 #include <App/Document.h>
@@ -49,14 +47,13 @@
 #include <Gui/SoFCSelection.h>
 #include <Gui/ViewProviderDocumentObject.h>
 
-#include <Mod/TechDraw/App/DrawProjGroup.h>
 
 #include "TaskProjGroup.h"
 #include "ViewProviderProjGroup.h"
 
 using namespace TechDrawGui;
 
-PROPERTY_SOURCE(TechDrawGui::ViewProviderProjGroup, Gui::ViewProviderDocumentObject)
+PROPERTY_SOURCE(TechDrawGui::ViewProviderProjGroup, TechDrawGui::ViewProviderDrawingView)
 
 //**************************************************************************
 // Construction/Destruction
@@ -165,8 +162,12 @@ std::vector<App::DocumentObject*> ViewProviderProjGroup::claimChildren(void) con
     }
 }
 
-
-TechDraw::DrawProjGroup* ViewProviderProjGroup::getObject() const
+TechDraw::DrawProjGroup* ViewProviderProjGroup::getViewObject() const
 {
     return dynamic_cast<TechDraw::DrawProjGroup*>(pcObject);
 }
+
+TechDraw::DrawProjGroup* ViewProviderProjGroup::getObject() const
+{
+    return getViewObject();
+}