Fix: Fixed duplicate initialization when resuming (#13261)

src/Files.App/Helpers/UI/ThemeHelper.cs

@@ -18,6 +18,7 @@ public static class ThemeHelper
 		private const string selectedAppThemeKey = "theme";
 		private static Window? currentApplicationWindow;
 		private static AppWindowTitleBar? titleBar;
+		private static bool isInitialized = false;
 
 		// Keep reference so it does not get optimized/garbage collected
 		public static UISettings UiSettings;
@@ -42,8 +43,13 @@ public static ElementTheme RootTheme
 			}
 		}
 
-		public static void Initialize()
+		public static bool Initialize()
 		{
+			if (isInitialized)
+				return false;
+
+			isInitialized = true;
+
 			// Save reference as this might be null when the user is in another app
 			currentApplicationWindow = MainWindow.Instance;
 
@@ -57,6 +63,8 @@ public static void Initialize()
 			// Registering to color changes, thus we notice when user changes theme system wide
 			UiSettings = new UISettings();
 			UiSettings.ColorValuesChanged += UiSettings_ColorValuesChanged;
+
+			return true;
 		}
 
 		public static void ApplyResources()

src/Files.App/ViewModels/MainPageViewModel.cs

@@ -273,7 +273,7 @@ public async Task OnNavigatedTo(NavigationEventArgs e)
 
 			//Initialize the static theme helper to capture a reference to this window
 			//to handle theme changes without restarting the app
-			ThemeHelper.Initialize();
+			var isInitialized = ThemeHelper.Initialize();
 
 			var parameter = e.Parameter;
 			var ignoreStartupSettings = false;
@@ -378,12 +378,15 @@ public async Task OnNavigatedTo(NavigationEventArgs e)
 					await AddNewTabByParam(tabArgs.InitialPageType, tabArgs.NavigationArg);
 			}
 
-			// Load the app theme resources
-			resourcesService.LoadAppResources(appearanceSettingsService);
+			if (isInitialized)
+			{
+				// Load the app theme resources
+				resourcesService.LoadAppResources(appearanceSettingsService);
 
-			await Task.WhenAll(
-				drivesViewModel.UpdateDrivesAsync(),
-				networkDrivesViewModel.UpdateDrivesAsync());
+				await Task.WhenAll(
+					drivesViewModel.UpdateDrivesAsync(),
+					networkDrivesViewModel.UpdateDrivesAsync());
+			}
 		}
 
 		public Task AddNewTabAsync()