// this is called on worker thread private object StartResourceInvalidationTest(object obj) { _win2.SetResourceReference(Window.TitleProperty, _windowTextResourceKey); if (_win2.Title.Equals(_windowTextResourceValue) == true) { _win2ResourceInvalidationPassed = true; } _win2.Close(); _win1.Dispatcher.BeginInvoke( DispatcherPriority.Background, new DispatcherOperationCallback(VerifyResourceInvalidationTestOnAppThread), null); return(null); }