Hide main settings window instead of closing (#17960)

* Hide main settings window instead of closing

* Proper closing

* Create Settings window hidden if opening OOBE/SCOOBE

src/settings-ui/Settings.UI/App.xaml.cs

@@ -149,9 +149,11 @@ protected override void OnLaunched(Microsoft.UI.Xaml.LaunchActivatedEventArgs ar
                 }
                 else
                 {
-                    // Create the Settings window so that it's fully initialized and
+                    // Create the Settings window hidden so that it's fully initialized and
                     // it will be ready to receive the notification if the user opens
                     // the Settings from the tray icon.
+                    settingsWindow = new MainWindow(true);
+
                     if (ShowOobe)
                     {
                         PowerToysTelemetry.Log.WriteEvent(new OobeStartedEvent());

src/settings-ui/Settings.UI/Helpers/NativeMethods.cs

@@ -15,6 +15,7 @@ public static class NativeMethods
         internal const int SPI_GETDESKWALLPAPER = 0x0073;
         internal const int SW_SHOWNORMAL = 1;
         internal const int SW_SHOWMAXIMIZED = 3;
+        internal const int SW_HIDE = 0;
 
         [DllImport("user32.dll")]
         internal static extern IntPtr GetActiveWindow();
@@ -44,6 +45,9 @@ public static class NativeMethods
         [DllImport("user32.dll")]
         public static extern int GetDpiForWindow(System.IntPtr hWnd);
 
+        [DllImport("user32.dll")]
+        public static extern bool IsWindowVisible(IntPtr hWnd);
+
         [DllImport("user32.dll")]
         public static extern bool AllowSetForegroundWindow(int dwProcessId);
 

src/settings-ui/Settings.UI/MainWindow.xaml.cs

@@ -22,7 +22,7 @@ namespace Microsoft.PowerToys.Settings.UI
     /// </summary>
     public sealed partial class MainWindow : Window
     {
-        public MainWindow()
+        public MainWindow(bool createHidden = false)
         {
             var bootTime = new System.Diagnostics.Stopwatch();
             bootTime.Start();
@@ -37,6 +37,11 @@ public MainWindow()
             appWindow.SetIcon("icon.ico");
 
             var placement = Utils.DeserializePlacementOrDefault(hWnd);
+            if (createHidden)
+            {
+                placement.ShowCmd = NativeMethods.SW_HIDE;
+            }
+
             NativeMethods.SetWindowPlacement(hWnd, ref placement);
 
             ResourceLoader loader = ResourceLoader.GetForViewIndependentUse();
@@ -105,12 +110,29 @@ public void NavigateToSection(System.Type type)
             ShellPage.Navigate(type);
         }
 
-        private void Window_Closed(object sender, WindowEventArgs args)
+        public void CloseHiddenWindow()
         {
-            App.ClearSettingsWindow();
+            var hWnd = WinRT.Interop.WindowNative.GetWindowHandle(this);
+            if (!NativeMethods.IsWindowVisible(hWnd))
+            {
+                Close();
+            }
+        }
 
+        private void Window_Closed(object sender, WindowEventArgs args)
+        {
             var hWnd = WinRT.Interop.WindowNative.GetWindowHandle(this);
             Utils.SerializePlacement(hWnd);
+
+            if (App.GetOobeWindow() == null)
+            {
+                App.ClearSettingsWindow();
+            }
+            else
+            {
+                args.Handled = true;
+                NativeMethods.ShowWindow(hWnd, NativeMethods.SW_HIDE);
+            }
         }
     }
 }

src/settings-ui/Settings.UI/OobeWindow.xaml.cs

@@ -104,6 +104,12 @@ private void OobeWindow_SizeChanged(object sender, WindowSizeChangedEventArgs ar
         private void Window_Closed(object sender, WindowEventArgs args)
         {
             App.ClearOobeWindow();
+
+            var mainWindow = App.GetSettingsWindow();
+            if (mainWindow != null)
+            {
+                mainWindow.CloseHiddenWindow();
+            }
         }
     }
 }