Deux

src/modules/Deux/UI/Microsoft.CommandPalette.UI.Services/KeyboardService.cs

@@ -42,9 +42,9 @@ public partial class KeyboardService : IDisposable
         _settingsService.SettingsChanged += SettingsChanged;
     }
 
-    public void SetProcessCommand(HWND hwnd, ProcessCommand processCommand)
+    public void SetProcessCommand(IntPtr hwnd, ProcessCommand processCommand)
     {
-        _hwnd = hwnd;
+        _hwnd = new HWND(hwnd);
         _keyboardListener.SetProcessCommand(processCommand);
         SetupHotkeys();
     }

src/modules/Deux/UI/Microsoft.CommandPalette.UI.Services/NavigationManager.cs

@@ -0,0 +1,9 @@
+// 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.
+
+namespace Microsoft.CommandPalette.UI.Services;
+
+internal class NavigationManager
+{
+}

src/modules/Deux/UI/Microsoft.CommandPalette.UI/Pages/ShellPage.xaml.cs

@@ -11,6 +11,7 @@ using Microsoft.CommandPalette.Extensions;
 using Microsoft.CommandPalette.UI.Models.Events;
 using Microsoft.CommandPalette.UI.Models.Messages;
 using Microsoft.CommandPalette.UI.Services;
+using Microsoft.CommandPalette.UI.Services.Helpers;
 using Microsoft.CommandPalette.UI.ViewModels;
 using Microsoft.CommandPalette.ViewModels;
 using Microsoft.Extensions.Logging;
@@ -160,6 +161,71 @@ public sealed partial class ShellPage : Microsoft.UI.Xaml.Controls.Page,
         });
     }
 
+    public void Receive(GoBackMessage message)
+    {
+        _ = DispatcherQueue.TryEnqueue(() => GoBack(message.WithAnimation, message.FocusSearch));
+    }
+
+    private void GoBack(bool withAnimation = true, bool focusSearch = true)
+    {
+        HideDetails();
+
+        viewModel.CancelNavigation();
+
+        // Note: That we restore the VM state below in RootFrame_Navigated call back after this occurs.
+        // In the future, we may want to manage the back stack ourselves vs. relying on Frame
+        // We could replace Frame with a ContentPresenter, but then have to manage transition animations ourselves.
+        // However, then we have more fine-grained control on the back stack, managing the VM cache, and not
+        // having that all be a black box, though then we wouldn't cache the XAML page itself, but sometimes that is a drawback.
+        // However, we do a good job here, see ForwardStack.Clear below, and BackStack.Clear above about managing that.
+        if (withAnimation)
+        {
+            RootFrame.GoBack();
+        }
+        else
+        {
+            RootFrame.GoBack(_noAnimation);
+        }
+
+        // Don't store pages we're navigating away from in the Frame cache
+        // TODO: In the future we probably want a short cache (3-5?) of recent VMs in case the user re-navigates
+        // back to a recent page they visited (like the Pokedex) so we don't have to reload it from  scratch.
+        // That'd be retrieved as we re-navigate in the PerformCommandMessage logic above
+        RootFrame.ForwardStack.Clear();
+
+        if (!RootFrame.CanGoBack)
+        {
+            viewModel.GoHome();
+        }
+
+        if (focusSearch)
+        {
+            SearchBox.Focus(Microsoft.UI.Xaml.FocusState.Programmatic);
+            SearchBox.SelectSearch();
+        }
+    }
+
+    public void Receive(GoHomeMessage message)
+    {
+        _ = DispatcherQueue.TryEnqueue(() => GoHome(withAnimation: message.WithAnimation, focusSearch: message.FocusSearch));
+    }
+
+    private void GoHome(bool withAnimation = true, bool focusSearch = true)
+    {
+        while (RootFrame.CanGoBack)
+        {
+            // don't focus on each step, just at the end
+            GoBack(withAnimation, focusSearch: false);
+        }
+
+        // focus search box, even if we were already home
+        if (focusSearch)
+        {
+            SearchBox.Focus(Microsoft.UI.Xaml.FocusState.Programmatic);
+            SearchBox.SelectSearch();
+        }
+    }
+
     public void Receive(ShowToastMessage message)
     {
         DispatcherQueue.TryEnqueue(() =>
@@ -242,21 +308,21 @@ public sealed partial class ShellPage : Microsoft.UI.Xaml.Controls.Page,
 
     public void Receive(ShowDetailsMessage message)
     {
-        if (ViewModel is not null &&
+        if (viewModel is not null &&
-            ViewModel.CurrentPage is not null)
+            viewModel.CurrentPage is not null)
         {
-            if (ViewModel.CurrentPage.PageContext.TryGetTarget(out var pageContext))
+            if (viewModel.CurrentPage.PageContext.TryGetTarget(out var pageContext))
             {
                 Task.Factory.StartNew(
                     () =>
                     {
                         // TERRIBLE HACK TODO GH #245
                         // There's weird wacky bugs with debounce currently.
-                        if (!ViewModel.IsDetailsVisible)
+                        if (!viewModel.IsDetailsVisible)
                         {
-                            ViewModel.Details = message.Details;
+                            viewModel.Details = message.Details;
                             PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(HasHeroImage)));
-                            ViewModel.IsDetailsVisible = true;
+                            viewModel.IsDetailsVisible = true;
                             return;
                         }
 
@@ -267,15 +333,15 @@ public sealed partial class ShellPage : Microsoft.UI.Xaml.Controls.Page,
                         _debounceTimer.Debounce(
                             () =>
                             {
-                                ViewModel.Details = message.Details;
+                                viewModel.Details = message.Details;
 
                                 // Trigger a re-evaluation of whether we have a hero image based on
                                 // the current theme
                                 PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(HasHeroImage)));
                             },
                             interval: TimeSpan.FromMilliseconds(50),
-                            immediate: ViewModel.IsDetailsVisible == false);
+                            immediate: viewModel.IsDetailsVisible == false);
-                        ViewModel.IsDetailsVisible = true;
+                        viewModel.IsDetailsVisible = true;
                     },
                     CancellationToken.None,
                     TaskCreationOptions.None,
@@ -290,8 +356,8 @@ public sealed partial class ShellPage : Microsoft.UI.Xaml.Controls.Page,
 
     private void HideDetails()
     {
-        ViewModel.Details = null;
+        viewModel.Details = null;
-        ViewModel.IsDetailsVisible = false;
+        viewModel.IsDetailsVisible = false;
     }
 
     public void Receive(ClearSearchMessage message) => SearchBox.ClearSearch();