How to refresh parent screens in lightswitch?

I want to refresh the search screens after adding new data from other s开发者_高级运维creens. I've tried doing

foreach (var parentScreen in this.Application.ActiveScreens.OfType<ScreenType>())
{
     //Invoke the refresh
     parentScreen.Details.Dispatcher.BeginInvoke(() => parentScreen.Details.Commands.Refresh.Execute());
}

but it doesn't seem to work in Beta 2

found it on http://social.msdn.microsoft.com/Forums/en-US/lightswitchgeneral/thread/cf86ad21-48fb-48f2-87d4-e5b15f8f361c#e6879629-145a-4b18-834c-ebee0cfe1473

Unfortunately the collection of ActiveScreens does not actually contain a set of Screen objects. It contains a proxy class that you can use to access the actual screen object (this is due to different threads running in different threads). Here is some sample code that achieves what you need.

  Microsoft.LightSwitch.Client.IActiveScreen searchScreen = Application.ActiveScreens.Where(a => a.Screen is SearchCustomers).FirstOrDefault();
  searchScreen.Screen.Details.Dispatcher.BeginInvoke(() => 
  {
    ((SearchCustomers)searchScreen.Screen).Customers.Refresh();
  });