CreateShell Method Can't Return RadWindow in Prism 7

Updated on Sep 15, 2025

Environment

Product Version	2019.1.220
Product	RadWindow for WPF

Description

Returning object of type RadWindow in the Prism 7 application CreateShell method causes an error.

Solution

Return null in CreateShell() method, and override OnInitialized() method to show the RadWindow.

C#

	public partial class App
	{
		protected override Window CreateShell()
		{
		    return null;
		}
		protected override void OnInitialized()
		{
		    // TelerikShell derives from RadWindow
		    TelerikShell shellWindow = Container.Resolve<TelerikShell>();
		    shellWindow.Show();
		    MainWindow = shellWindow.ParentOfType<Window>();
	
		    RegionManager.SetRegionManager(MainWindow, Container.Resolve<IRegionManager>());
		    RegionManager.UpdateRegions();
		    InitializeModules();
		    base.OnInitialized();
		}
		protected override void RegisterTypes(IContainerRegistry containerRegistry)
		{

		}
	}