Question

I have an event subscription from PRISM in Background Thread. After Login I load several Application related Data.
Also I try to resolve the MainMenu from Unity Container.

MainMenu mainMenu = container.Resolve<MainMenu>();

This will end with an exception. It must be called from an STA Thread because the operations are GUI related.
This seems totally understandable, but

1. If I use the Dispatcher there is no Exception but it blocks the UI Thread, thats not what I want.
2. Using another BackgroundWorker or Task Factory wont solve the problem, because its still in background Thread.

So how do I load GUI related stuff inside a background Thread?

Answer 1

Try creating a thread with the STA ApartmentState:

Thread uiThread = new Thread(() =>
{
    mainMenu = container.Resolve<MainMenu>();

    // Allow the main UI thread to proceed 
    System.Windows.Threading.Dispatcher.Run();     
});               
uiThread.SetApartmentState(ApartmentState.STA);
uiThread.IsBackground = true;
uiThread.Start();