Fix: Fixed potential COMException when setting the wallpaper (#13921)

Author: yaira2

src/Files.App/Strings/en-US/Resources.resw

@@ -3608,4 +3608,7 @@
   <data name="FailedToRestore" xml:space="preserve">
     <value>Failed to restore items from Recycle Bin</value>
   </data>
+  <data name="FailedToSetBackground" xml:space="preserve">
+    <value>Failed to set the background wallpaper</value>
+  </data>
 </root>

src/Files.App/Utils/Global/WallpaperHelpers.cs

@@ -1,10 +1,9 @@
 // Copyright (c) 2023 Files Community
 // Licensed under the MIT License. See the LICENSE.
 
-using System;
-using System.Linq;
-using System.Threading.Tasks;
+using Microsoft.UI.Xaml.Controls;
 using Vanara.PInvoke;
+using Windows.Foundation.Metadata;
 using Windows.Storage;
 using Windows.System.UserProfile;
 
@@ -14,12 +13,20 @@ public static class WallpaperHelpers
 	{
 		public static async Task SetAsBackgroundAsync(WallpaperType type, string filePath)
 		{
+
 			if (type == WallpaperType.Desktop)
 			{
-				// Set the desktop background
-				var wallpaper = (Shell32.IDesktopWallpaper)new Shell32.DesktopWallpaper();
-				wallpaper.GetMonitorDevicePathAt(0, out var monitorId);
-				wallpaper.SetWallpaper(monitorId, filePath);
+				try
+				{
+					// Set the desktop background
+					var wallpaper = (Shell32.IDesktopWallpaper)new Shell32.DesktopWallpaper();
+					wallpaper.GetMonitorDevicePathAt(0, out var monitorId);
+					wallpaper.SetWallpaper(monitorId, filePath);
+				}
+				catch (Exception ex)
+				{
+					ShowErrorPrompt(ex.Message);
+				}
 			}
 			else if (type == WallpaperType.LockScreen)
 			{
@@ -34,15 +41,37 @@ public static void SetSlideshow(string[] filePaths)
 			if (filePaths is null || !filePaths.Any())
 				return;
 
-			var idList = filePaths.Select(Shell32.IntILCreateFromPath).ToArray();
-			Shell32.SHCreateShellItemArrayFromIDLists((uint)idList.Length, idList.ToArray(), out var shellItemArray);
+			try
+			{
+				var idList = filePaths.Select(Shell32.IntILCreateFromPath).ToArray();
+				Shell32.SHCreateShellItemArrayFromIDLists((uint)idList.Length, idList.ToArray(), out var shellItemArray);
+
+				// Set SlideShow
+				var wallpaper = (Shell32.IDesktopWallpaper)new Shell32.DesktopWallpaper();
+				wallpaper.SetSlideshow(shellItemArray);
+
+				// Set wallpaper to fill desktop.
+				wallpaper.SetPosition(Shell32.DESKTOP_WALLPAPER_POSITION.DWPOS_FILL);
+			}
+			catch (Exception ex)
+			{
+				ShowErrorPrompt(ex.Message);
+			}
+		}
+
+		private static async void ShowErrorPrompt(string exception)
+		{
+			var errorDialog = new ContentDialog()
+			{
+				Title = "FailedToSetBackground".GetLocalizedResource(),
+				Content = exception,
+				PrimaryButtonText = "OK".GetLocalizedResource(),
+			};
 
-			// Set SlideShow
-			var wallpaper = (Shell32.IDesktopWallpaper)new Shell32.DesktopWallpaper();
-			wallpaper.SetSlideshow(shellItemArray);
+			if (ApiInformation.IsApiContractPresent("Windows.Foundation.UniversalApiContract", 8))
+				errorDialog.XamlRoot = MainWindow.Instance.Content.XamlRoot;
 
-			// Set wallpaper to fill desktop.
-			wallpaper.SetPosition(Shell32.DESKTOP_WALLPAPER_POSITION.DWPOS_FILL);
+			await errorDialog.TryShowAsync();
 		}
 	}
 }