Enable drag region workaround

CoreAppUWP/CoreAppUWP.csproj

@@ -12,7 +12,7 @@
     <PublishProfile>win10-$(Platform).pubxml</PublishProfile>
     <RepositoryUrl>https://github.com/wherewhere/CoreAppUWP</RepositoryUrl>
     <RuntimeIdentifiers>win-x86;win-x64;win-arm64</RuntimeIdentifiers>
-    <TargetFramework>net8.0-windows10.0.22621.0</TargetFramework>
+    <TargetFramework>net7.0-windows10.0.22621.0</TargetFramework>
     <TargetPlatformMinVersion>10.0.17763.0</TargetPlatformMinVersion>
     <TrimMode>partial</TrimMode>
     <UseWinUI>True</UseWinUI>

CoreAppUWP/Helpers/UIHelper.cs

@@ -3,13 +3,20 @@
 using System.Threading;
 using System.Threading.Tasks;
 using Windows.Foundation.Metadata;
+using Windows.Graphics.Display;
 
 namespace CoreAppUWP.Helpers
 {
     public static class UIHelper
     {
         public static bool HasStatusBar => ApiInformation.IsTypePresent("Windows.UI.ViewManagement.StatusBar");
 
+        public static int GetActualPixel(this double pixel)
+        {
+            double currentDpi = DisplayInformation.GetForCurrentView().RawPixelsPerViewPixel;
+            return Convert.ToInt32(pixel * currentDpi);
+        }
+
         public static string ExceptionToMessage(this Exception ex)
         {
             StringBuilder builder = new();

CoreAppUWP/Helpers/WindowHelper.cs

@@ -1,11 +1,16 @@
 using CoreAppUWP.Common;
+using Microsoft.UI;
+using Microsoft.UI.Windowing;
 using Microsoft.UI.Xaml;
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
 using Windows.ApplicationModel.Core;
 using Windows.UI.Core;
 using Windows.UI.ViewManagement;
+using Windows.Win32.Foundation;
+using Windows.Win32.System.WinRT;
+using WinRT;
 
 namespace CoreAppUWP.Helpers
 {
@@ -48,6 +53,24 @@ public static void TrackWindow(this Window window)
             }
         }
 
+        public static AppWindow GetAppWindow(this CoreWindow window)
+        {
+            if (!ActiveAppWindows.TryGetValue(window, out AppWindow appWindow))
+            {
+                HWND handle = window.As<ICoreWindowInterop>().WindowHandle;
+                WindowId id = Win32Interop.GetWindowIdFromWindow(handle);
+                appWindow = AppWindow.GetFromWindowId(id);
+                window.Closed += (sender, args) =>
+                {
+                    ActiveAppWindows.Remove(window);
+                    window = null;
+                };
+                ActiveAppWindows[window] = appWindow;
+            }
+            return appWindow;
+        }
+
         public static Dictionary<CoreDispatcher, Window> ActiveWindows { get; } = [];
+        public static Dictionary<CoreWindow, AppWindow> ActiveAppWindows { get; } = [];
     }
 }

CoreAppUWP/Pages/MainPage.xaml

@@ -16,7 +16,8 @@
             Height="48"
             VerticalAlignment="Top"
             Canvas.ZIndex="1"
-            IsHitTestVisible="True">
+            IsHitTestVisible="True"
+            SizeChanged="CustomTitleBar_SizeChanged">
             <Grid.ColumnDefinitions>
                 <ColumnDefinition x:Name="LeftPaddingColumn" Width="0" />
                 <ColumnDefinition Width="Auto" />
@@ -56,10 +57,12 @@
                     TextTrimming="CharacterEllipsis"
                     TextWrapping="NoWrap" />
             </Grid>
-            <Grid
+            <Border
                 x:Name="DragRegion"
                 Grid.Column="1"
-                Grid.ColumnSpan="3"
+                Grid.ColumnSpan="4"
+                HorizontalAlignment="Stretch"
+                VerticalAlignment="Stretch"
                 Background="{ThemeResource SystemControlTransparentBrush}" />
         </Grid>
         <NavigationView

CoreAppUWP/Pages/MainPage.xaml.cs

@@ -8,8 +8,10 @@
 using System.Collections.Generic;
 using System.Linq;
 using Windows.ApplicationModel.Core;
+using Windows.Graphics;
 using Windows.UI.Core;
 
+
 // To learn more about WinUI, the WinUI project structure,
 // and more about our project templates, see: http://aka.ms/winui-project-info.
 
@@ -180,5 +182,11 @@ private void System_BackRequested(object sender, BackRequestedEventArgs e)
                 e.Handled = TryGoBack();
             }
         }
+
+        private void CustomTitleBar_SizeChanged(object sender, SizeChangedEventArgs e)
+        {
+            RectInt32 Rect = new((ActualWidth - DragRegion.ActualWidth).GetActualPixel(), 0, DragRegion.ActualWidth.GetActualPixel(), DragRegion.ActualHeight.GetActualPixel());
+            Window.Current.CoreWindow.GetAppWindow().TitleBar.SetDragRectangles([Rect]);
+        }
     }
 }