1  // Copyright (c) Microsoft Corporation
 2  // The Microsoft Corporation licenses this file to you under the MIT license.
 3  // See the LICENSE file in the project root for more information.
 4  
 5  using Microsoft.CmdPal.Core.ViewModels;
 6  using Microsoft.UI.Dispatching;
 7  using Microsoft.UI.Xaml.Controls;
 8  using Microsoft.UI.Xaml.Navigation;
 9  
10  namespace Microsoft.CmdPal.UI.Pages;
11  
12  /// <summary>
13  /// We use this page to do initialization of our extensions and cache loading to hydrate our ViewModels.
14  /// </summary>
15  public sealed partial class LoadingPage : Page
16  {
17      private readonly DispatcherQueue _queue = DispatcherQueue.GetForCurrentThread();
18  
19      public LoadingPage()
20      {
21          this.InitializeComponent();
22      }
23  
24      protected override void OnNavigatedTo(NavigationEventArgs e)
25      {
26          if (e.Parameter is not AsyncNavigationRequest request)
27          {
28              throw new InvalidOperationException($"Invalid navigation parameter: {nameof(e.Parameter)} must be {nameof(AsyncNavigationRequest)}");
29          }
30  
31          if (request.TargetViewModel is not ShellViewModel shellVM)
32          {
33              throw new InvalidOperationException($"Invalid navigation target: AsyncNavigationRequest.{nameof(AsyncNavigationRequest.TargetViewModel)} must be {nameof(ShellViewModel)}");
34          }
35  
36          // This will load the built-in commands, then navigate to the main page.
37          // Once the mainpage loads, we'll start loading extensions.
38          shellVM.LoadCommand.Execute(null);
39  
40          _ = Task.Run(async () =>
41          {
42              await shellVM.LoadCommand.ExecutionTask!;
43  
44              if (shellVM.LoadCommand.ExecutionTask.Status != TaskStatus.RanToCompletion)
45              {
46                  // TODO: Handle failure case
47              }
48          });
49  
50          base.OnNavigatedTo(e);
51      }
52  }