is this a real PR that needs to be merged? or is this branch stale?

vertical_tasks/App.xaml.cpp

@@ -2,45 +2,50 @@
 
 #include "App.xaml.h"
 #include "MainWindow.xaml.h"
+#include <microsoft.ui.xaml.window.h>
 
-using namespace winrt;
-using namespace Windows::Foundation;
-using namespace Microsoft::UI::Xaml;
-using namespace Microsoft::UI::Xaml::Controls;
-using namespace Microsoft::UI::Xaml::Navigation;
-using namespace vertical_tasks;
-using namespace vertical_tasks::implementation;
-
-// To learn more about WinUI, the WinUI project structure,
-// and more about our project templates, see: http://aka.ms/winui-project-info.
+namespace winrt
+{
+    using namespace Windows::Foundation;
+    using namespace Microsoft::UI::Xaml;
+    using namespace Microsoft::UI::Xaml::Controls;
+    using namespace Microsoft::UI::Xaml::Navigation;
+    using namespace vertical_tasks;
+}
 
-/// <summary>
-/// Initializes the singleton application object.  This is the first line of authored code
-/// executed, and as such is the logical equivalent of main() or WinMain().
-/// </summary>
-App::App()
+namespace winrt::vertical_tasks::implementation
 {
-    InitializeComponent();
+    // To learn more about WinUI, the WinUI project structure,
+    // and more about our project templates, see: http://aka.ms/winui-project-info.
 
-#if defined _DEBUG && !defined DISABLE_XAML_GENERATED_BREAK_ON_UNHANDLED_EXCEPTION
-    UnhandledException([this](IInspectable const&, UnhandledExceptionEventArgs const& e)
+    /// <summary>
+    /// Initializes the singleton application object.  This is the first line of authored code
+    /// executed, and as such is the logical equivalent of main() or WinMain().
+    /// </summary>
+    App::App()
     {
-        if (IsDebuggerPresent())
-        {
-            auto errorMessage = e.Message();
-            __debugbreak();
-        }
-    });
+        InitializeComponent();
+
+#if defined _DEBUG && !defined DISABLE_XAML_GENERATED_BREAK_ON_UNHANDLED_EXCEPTION
+        UnhandledException([this](winrt::IInspectable const&, winrt::UnhandledExceptionEventArgs const& e)
+            {
+                if (IsDebuggerPresent())
+                {
+                    auto errorMessage = e.Message();
+                    __debugbreak();
+                }
+            });
 #endif
-}
+    }
 
-/// <summary>
-/// Invoked when the application is launched normally by the end user.  Other entry points
-/// will be used such as when the application is launched to open a specific file.
-/// </summary>
-/// <param name="e">Details about the launch request and process.</param>
-void App::OnLaunched(LaunchActivatedEventArgs const&)
-{
-    window = make<MainWindow>();
-    window.Activate();
+    /// <summary>
+    /// Invoked when the application is launched normally by the end user.  Other entry points
+    /// will be used such as when the application is launched to open a specific file.
+    /// </summary>
+    /// <param name="e">Details about the launch request and process.</param>
+    void App::OnLaunched(winrt::LaunchActivatedEventArgs const&)
+    {
+        window = winrt::make<winrt::vertical_tasks::implementation::MainWindow>();
+        window.Activate();
+    }
 }

vertical_tasks/MainWindow.idl

@@ -1,10 +1,21 @@
 namespace vertical_tasks
 {
+    [default_interface]
+    runtimeclass TaskVM : Windows.UI.Xaml.Data.INotifyPropertyChanged
+    {
+        TaskVM(UInt64 hwnd);
+        String Title{ get; };
+        Microsoft.UI.Xaml.Controls.IconSource IconSource{ get; };
+
+        void Select();
+        void Close();
+
+    }
+
     [default_interface]
     runtimeclass MainWindow : Microsoft.UI.Xaml.Window
     {
         MainWindow();
-        Int32 MyProperty;
-        Windows.Foundation.Collections.IObservableVector<IInspectable> WindowTitles{ get; };
+        Windows.Foundation.Collections.IObservableVector<Object> Tasks{ get; };
     }
 }