quit event loop after closing main window if not started by an extern host application

src/Gui/Application.cpp

@@ -1722,6 +1722,7 @@ void Application::runApplication(void)
 
     Application app(true);
     MainWindow mw;
+    mw.setProperty("QuitOnClosed", true);
 
     // allow to disable version number
     ParameterGrp::handle hGen = App::GetApplication().GetParameterGroupByPath("User parameter:BaseApp/Preferences/General");

src/Gui/MainWindow.cpp

@@ -976,7 +976,8 @@ void MainWindow::closeEvent (QCloseEvent * e)
         }
 
         /*emit*/ mainWindowClosed();
-        qApp->quit(); // stop the event loop
+        if (this->property("QuitOnClosed").isValid())
+            qApp->quit(); // stop the event loop
     }
 }