Fix DPI jump on window close in net462 #1626

QuickLook/App.xaml.cs

@@ -20,6 +20,7 @@ using QuickLook.Common.Helpers;
 using QuickLook.Helpers;
 using QuickLook.NativeMethods;
 using System;
+using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using System.Reflection;
@@ -28,13 +29,9 @@ using System.Threading.Tasks;
 using System.Windows;
 using Wpf.Ui.Appearance;
 using Wpf.Ui.Violeta.Appearance;
-using Wpf.Ui.Violeta.Win32;
 
 namespace QuickLook;
 
-/// <summary>
-///     Interaction logic for App.xaml
-/// </summary>
 public partial class App : Application
 {
     public static readonly string LocalDataPath = SettingHelper.LocalDataPath;
@@ -51,6 +48,19 @@ public partial class App : Application
     private bool _cleanExit = true;
     private Mutex _isRunning;
 
+    static App()
+    {
+        // Explicitly set to PerMonitor to avoid being overridden by the system
+        if (SHCore.SetProcessDpiAwareness(SHCore.PROCESS_DPI_AWARENESS.PROCESS_PER_MONITOR_DPI_AWARE) is uint result)
+        {
+            Debug.WriteLine(
+                result == 0 ?
+                "DPI Awareness applied successfully" :
+                $"DPI Awareness manual setup failed. Error Code: {result}"
+            );
+        }
+    }
+
     protected override void OnStartup(StartupEventArgs e)
     {
         AppDomain.CurrentDomain.UnhandledException += (sender, args) =>
@@ -71,7 +81,6 @@ public partial class App : Application
             ThemeManager.Apply(OSThemeHelper.AppsUseDarkTheme() ? ApplicationTheme.Dark : ApplicationTheme.Light);
         UxTheme.ApplyPreferredAppMode();
 
-        DpiAware.SetProcessDpiAwareness();
         base.OnStartup(e);
     }
 

QuickLook/NativeMethods/SHCore.cs

@@ -0,0 +1,16 @@
+using System.Runtime.InteropServices;
+
+namespace QuickLook.NativeMethods;
+
+internal static class SHCore
+{
+    public enum PROCESS_DPI_AWARENESS
+    {
+        PROCESS_DPI_UNAWARE,
+        PROCESS_SYSTEM_DPI_AWARE,
+        PROCESS_PER_MONITOR_DPI_AWARE
+    }
+
+    [DllImport("shcore.dll")]
+    public static extern uint SetProcessDpiAwareness(PROCESS_DPI_AWARENESS awareness);
+}

QuickLook/QuickLook.csproj

@@ -111,7 +111,7 @@
         <PackageReference Include="System.Runtime.CompilerServices.Unsafe" Version="6.0.0">
             <PrivateAssets>all</PrivateAssets>
         </PackageReference>
-        <PackageReference Include="UnblockZoneIdentifier " Version="1.0.0">
+        <PackageReference Include="UnblockZoneIdentifier" Version="1.0.0">
             <PrivateAssets>all</PrivateAssets>
         </PackageReference>
     </ItemGroup>

QuickLook/ViewerWindow.xaml.cs

@@ -20,6 +20,7 @@ using QuickLook.Common.Helpers;
 using QuickLook.Common.Plugin;
 using QuickLook.Helpers;
 using System;
+using System.Runtime.InteropServices;
 using System.Windows;
 using System.Windows.Input;
 using System.Windows.Media.Animation;
@@ -108,6 +109,15 @@ public partial class ViewerWindow : Window
         buttonShare.ToolTip = TranslationHelper.Get("MW_Share");
     }
 
+    public new void Close()
+    {
+        // Workaround to prevent DPI jump animation when closing window in .NET Framework 4.6.2
+        // Safe to remove this line if QuickLook no longer targets .NET Framework 4.6.2
+        Hide();
+
+        base.Close();
+    }
+
     public override void OnApplyTemplate()
     {
         base.OnApplyTemplate();