Fix: Fixed COMException in MainWindow.EnsureWindowIsInitialized (#15932)

Author: hishitetsu

src/Files.App/MainWindow.xaml.cs

@@ -7,6 +7,7 @@
 using Microsoft.UI.Xaml.Controls;
 using Microsoft.UI.Xaml.Media.Animation;
 using Microsoft.UI.Xaml.Navigation;
+using System.Runtime.InteropServices;
 using Windows.ApplicationModel.Activation;
 using Windows.Storage;
 using WinUIEx;
@@ -58,13 +59,16 @@ public void ShowSplashScreen()
 		{
 			var rootFrame = EnsureWindowIsInitialized();
 
-			rootFrame.Navigate(typeof(SplashScreenPage));
+			rootFrame?.Navigate(typeof(SplashScreenPage));
 		}
 
 		public async Task InitializeApplicationAsync(object activatedEventArgs)
 		{
 			var rootFrame = EnsureWindowIsInitialized();
 
+			if (rootFrame is null)
+				return;
+
 			// Set system backdrop
 			SystemBackdrop = new AppSystemBackdrop();
 
@@ -209,22 +213,29 @@ public async Task InitializeApplicationAsync(object activatedEventArgs)
 				Instance.Restore(); // Restore window if minimized
 		}
 
-		public Frame EnsureWindowIsInitialized()
+		private Frame? EnsureWindowIsInitialized()
 		{
-			// NOTE:
-			//  Do not repeat app initialization when the Window already has content,
-			//  just ensure that the window is active
-			if (Instance.Content is not Frame rootFrame)
+			try
 			{
-				// Create a Frame to act as the navigation context and navigate to the first page
-				rootFrame = new() { CacheSize = 1 };
-				rootFrame.NavigationFailed += OnNavigationFailed;
+				// NOTE:
+				//  Do not repeat app initialization when the Window already has content,
+				//  just ensure that the window is active
+				if (Instance.Content is not Frame rootFrame)
+				{
+					// Create a Frame to act as the navigation context and navigate to the first page
+					rootFrame = new() { CacheSize = 1 };
+					rootFrame.NavigationFailed += OnNavigationFailed;
 
-				// Place the frame in the current Window
-				Instance.Content = rootFrame;
-			}
+					// Place the frame in the current Window
+					Instance.Content = rootFrame;
+				}
 
-			return rootFrame;
+				return rootFrame;
+			}
+			catch (COMException)
+			{
+				return null;
+			}
 		}
 
 		/// <summary>