move Automation Notification functionality to UIHelper, implement UIHelper in ListPage and SettingsWindow (#41016)

## Summary of the Pull Request
Fixed #41014 and it overlapped with #40761, so I made a UIHelper
patterning off of WinUI Gallery's
[UIHelpder](0576fb508a/WinUIGallery/Helpers/UIHelper.cs (L63))

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## PR Checklist

- [x] Closes: #41014
- [x] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
- [ ] [YML for CI
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
- [ ] [YML for signed
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

<!-- Provide a more detailed description of the PR, other things fixed,
or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments

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wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed



https://github.com/user-attachments/assets/011ee8c1-baaf-47fc-b8f8-ee489b01702b

src/modules/cmdpal/Microsoft.CmdPal.UI/ExtViews/ListPage.xaml.cs

@@ -7,6 +7,7 @@ using CommunityToolkit.Mvvm.Messaging;
 using ManagedCommon;
 using Microsoft.CmdPal.Core.ViewModels;
 using Microsoft.CmdPal.Core.ViewModels.Messages;
+using Microsoft.CmdPal.UI.Helpers;
 using Microsoft.CmdPal.UI.Messages;
 using Microsoft.CmdPal.UI.ViewModels;
 using Microsoft.Extensions.DependencyInjection;
@@ -162,11 +163,11 @@ public sealed partial class ListPage : Page,
             if (listViewPeer is not null && li is not null)
             {
                 var notificationText = li.Title;
-                listViewPeer.RaiseNotificationEvent(
-                    Microsoft.UI.Xaml.Automation.Peers.AutomationNotificationKind.Other,
-                    Microsoft.UI.Xaml.Automation.Peers.AutomationNotificationProcessing.MostRecent,
-                    notificationText,
-                    "CommandPaletteSelectedItemChanged");
+
+                UIHelper.AnnounceActionForAccessibility(
+                     ItemsList,
+                     notificationText,
+                     "CommandPaletteSelectedItemChanged");
             }
         }
     }

src/modules/cmdpal/Microsoft.CmdPal.UI/Helpers/UIHelper.cs

@@ -0,0 +1,32 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Automation.Peers;
+
+namespace Microsoft.CmdPal.UI.Helpers;
+
+public static partial class UIHelper
+{
+    static UIHelper()
+    {
+    }
+
+    public static void AnnounceActionForAccessibility(UIElement ue, string announcement, string activityID)
+    {
+        if (FrameworkElementAutomationPeer.FromElement(ue) is AutomationPeer peer)
+        {
+            peer.RaiseNotificationEvent(
+                AutomationNotificationKind.ActionCompleted,
+                AutomationNotificationProcessing.ImportantMostRecent,
+                announcement,
+                activityID);
+        }
+    }
+}

src/modules/cmdpal/Microsoft.CmdPal.UI/Settings/SettingsWindow.xaml

@@ -25,17 +25,11 @@
             <RowDefinition Height="*" />
         </Grid.RowDefinitions>
         <!--  TO DO: Replace this with WinUI TitleBar once that ships.  -->
-        <Button
-            x:Name="PaneToggleBtn"
-            Width="48"
-            HorizontalAlignment="Left"
-            VerticalAlignment="Center"
-            Click="PaneToggleBtn_Click"
-            Style="{StaticResource PaneToggleButtonStyle}" />
         <StackPanel
             x:Name="AppTitleBar"
             Grid.Row="0"
             Height="48"
+            Margin="16,0,0,0"
             Orientation="Horizontal">
             <Image
                 Width="16"

src/modules/cmdpal/Microsoft.CmdPal.UI/Settings/SettingsWindow.xaml.cs

@@ -10,6 +10,7 @@ using Microsoft.CmdPal.UI.ViewModels;
 using Microsoft.CmdPal.UI.ViewModels.Messages;
 using Microsoft.UI.Windowing;
 using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Automation.Peers;
 using Microsoft.UI.Xaml.Controls;
 using WinUIEx;
 using RS_ = Microsoft.CmdPal.UI.Helpers.ResourceLoaderInstance;
@@ -22,6 +23,9 @@ public sealed partial class SettingsWindow : WindowEx,
 {
     public ObservableCollection<Crumb> BreadCrumbs { get; } = [];
 
+    // Gets or sets optional action invoked after NavigationView is loaded.
+    public Action NavigationViewLoaded { get; set; } = () => { };
+
     public SettingsWindow()
     {
         this.InitializeComponent();
@@ -35,10 +39,33 @@ public sealed partial class SettingsWindow : WindowEx,
         WeakReferenceMessenger.Default.Register<QuitMessage>(this);
     }
 
+    // Handles NavigationView loaded event.
+    // Sets up initial navigation and accessibility notifications.
     private void NavView_Loaded(object sender, RoutedEventArgs e)
     {
+        // Delay necessary to ensure NavigationView visual state can match navigation
+        Task.Delay(500).ContinueWith(_ => this.NavigationViewLoaded?.Invoke(), TaskScheduler.FromCurrentSynchronizationContext());
+
         NavView.SelectedItem = NavView.MenuItems[0];
         Navigate("General");
+
+        if (sender is NavigationView navigationView)
+        {
+            // Register for pane open/close changes to announce to screen readers
+            navigationView.RegisterPropertyChangedCallback(NavigationView.IsPaneOpenProperty, AnnounceNavigationPaneStateChanged);
+        }
+    }
+
+    // Announces navigation pane open/close state to screen readers for accessibility.
+    private void AnnounceNavigationPaneStateChanged(DependencyObject sender, DependencyProperty dp)
+    {
+        if (sender is NavigationView navigationView)
+        {
+            UIHelper.AnnounceActionForAccessibility(
+            ue: (UIElement)sender,
+            (sender as NavigationView)?.IsPaneOpen == true ? RS_.GetString("NavigationPaneOpened") : RS_.GetString("NavigationPaneClosed"),
+            "NavigationViewPaneIsOpenChangeNotificationId");
+        }
     }
 
     private void NavView_ItemInvoked(NavigationView sender, NavigationViewItemInvokedEventArgs args)
@@ -109,24 +136,15 @@ public sealed partial class SettingsWindow : WindowEx,
         WeakReferenceMessenger.Default.UnregisterAll(this);
     }
 
-    private void PaneToggleBtn_Click(object sender, RoutedEventArgs e)
-    {
-        NavView.IsPaneOpen = !NavView.IsPaneOpen;
-    }
-
     private void NavView_DisplayModeChanged(NavigationView sender, NavigationViewDisplayModeChangedEventArgs args)
     {
         if (args.DisplayMode == NavigationViewDisplayMode.Compact || args.DisplayMode == NavigationViewDisplayMode.Minimal)
         {
-            PaneToggleBtn.Visibility = Visibility.Visible;
             NavView.IsPaneToggleButtonVisible = false;
-            AppTitleBar.Margin = new Thickness(48, 0, 0, 0);
         }
         else
         {
-            PaneToggleBtn.Visibility = Visibility.Collapsed;
             NavView.IsPaneToggleButtonVisible = true;
-            AppTitleBar.Margin = new Thickness(16, 0, 0, 0);
         }
     }
 

src/modules/cmdpal/Microsoft.CmdPal.UI/Strings/en-us/Resources.resw

@@ -435,4 +435,10 @@ Right-click to remove the key combination, thereby deactivating the shortcut.</v
   <data name="StatusMessagesButton.[using:Microsoft.UI.Xaml.Controls]ToolTipService.ToolTip" xml:space="preserve">
     <value>Show status messages</value>
   </data>
+  <data name="NavigationPaneClosed" xml:space="preserve">
+    <value>Navigation pane closed</value>
+  </data>
+  <data name="NavigationPageOpened" xml:space="preserve">
+    <value>Navigation page opened</value>
+  </data>
 </root>