Better Dark Mode & Image Viewer Toggle Fixes

QuickLook.Plugin/QuickLook.Plugin.ImageViewer/ImagePanel.xaml

@@ -1,4 +1,4 @@
-<UserControl x:Class="QuickLook.Plugin.ImageViewer.ImagePanel"
+<UserControl x:Class="QuickLook.Plugin.ImageViewer.ImagePanel"
              xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
              xmlns:animatedImage="clr-namespace:QuickLook.Plugin.ImageViewer.AnimatedImage"
@@ -24,7 +24,7 @@
             <Rectangle.Style>
                 <Style>
                     <Style.Triggers>
-                        <DataTrigger Binding="{Binding ElementName=imagePanel, Path=Theme}" Value="{x:Static plugin:Themes.Dark}">
+                        <DataTrigger Binding="{Binding ElementName=imagePanel, Path=CanvasTheme}" Value="{x:Static plugin:Themes.Dark}">
                             <Setter Property="Rectangle.Fill">
                                 <Setter.Value>
                                     <ImageBrush AlignmentY="Top"
@@ -38,7 +38,7 @@
                                 </Setter.Value>
                             </Setter>
                         </DataTrigger>
-                        <DataTrigger Binding="{Binding ElementName=imagePanel, Path=Theme}" Value="{x:Static plugin:Themes.Light}">
+                        <DataTrigger Binding="{Binding ElementName=imagePanel, Path=CanvasTheme}" Value="{x:Static plugin:Themes.Light}">
                             <Setter Property="Rectangle.Fill">
                                 <Setter.Value>
                                     <ImageBrush AlignmentY="Top"

QuickLook.Plugin/QuickLook.Plugin.ImageViewer/ImagePanel.xaml.cs

@@ -1,4 +1,4 @@
-// Copyright © 2017-2026 QL-Win Contributors
+// Copyright © 2017-2026 QL-Win Contributors
 //
 // This file is part of QuickLook program.
 //
@@ -107,6 +107,7 @@ internal ImagePanel(ContextObject context, MetaProvider meta) : this()
 
         ShowMeta();
         Theme = ContextObject.Theme;
+        CanvasTheme = (Themes)SettingHelper.Get("LastCanvasTheme", (int)Theme, "QuickLook.Plugin.ImageViewer");
     }
 
     public bool ZoomWithControlKey
@@ -140,6 +141,17 @@ public Themes Theme
         }
     }
 
+    private Themes _canvasTheme = Themes.Dark;
+    public Themes CanvasTheme
+    {
+        get => _canvasTheme;
+        set
+        {
+            _canvasTheme = value;
+            OnPropertyChanged();
+        }
+    }
+
     public BitmapScalingMode RenderMode
     {
         get => _renderMode;
@@ -381,9 +393,9 @@ private void OnReverseColorOnClick(object sender, RoutedEventArgs e)
 
     private void OnBackgroundColourOnClick(object sender, RoutedEventArgs e)
     {
-        Theme = Theme == Themes.Dark ? Themes.Light : Themes.Dark;
+        CanvasTheme = CanvasTheme == Themes.Dark ? Themes.Light : Themes.Dark;
 
-        SettingHelper.Set("LastTheme", (int)Theme, "QuickLook.Plugin.ImageViewer");
+        SettingHelper.Set("LastCanvasTheme", (int)CanvasTheme, "QuickLook.Plugin.ImageViewer");
     }
 
     private void ShowMeta()

QuickLook/App.xaml.cs

@@ -227,8 +227,9 @@ protected override void OnStartup(StartupEventArgs e)
         // Therefore, the time-consuming initialization code can't be placed before `OnStartup`
         base.OnStartup(e);
 
-        // Set initial theme based on system settings
-        ThemeManager.Apply(OSThemeHelper.AppsUseDarkTheme() ? ApplicationTheme.Dark : ApplicationTheme.Light);
+        // Set initial theme based on system or user settings
+        var appTheme = SettingHelper.Get("AppTheme", 0, "QuickLook");
+        SetTheme(appTheme);
 
         // Initialize MessageBox patching
         MessageBoxPatcher.Initialize();
@@ -346,4 +347,20 @@ private void RunListener(StartupEventArgs e)
         KeystrokeDispatcher.GetInstance();
         PipeServerManager.GetInstance();
     }
+
+    public static void SetTheme(int theme)
+    {
+        switch (theme)
+        {
+            case 1:
+                ThemeManager.Apply(ApplicationTheme.Light);
+                break;
+            case 2:
+                ThemeManager.Apply(ApplicationTheme.Dark);
+                break;
+            default:
+                ThemeManager.Apply(OSThemeHelper.AppsUseDarkTheme() ? ApplicationTheme.Dark : ApplicationTheme.Light);
+                break;
+        }
+    }
 }

QuickLook/TrayIconManager.cs

@@ -38,6 +38,7 @@ internal partial class TrayIconManager : IDisposable
 
     private readonly TrayMenuItem _itemAutorun = null!;
     private readonly TrayMenuItem _itemCloseOnLostFocus = null!;
+    private readonly TrayMenuItem _itemThemeCycle = null!;
 
     private TrayIconManager()
     {
@@ -70,6 +71,17 @@ private TrayIconManager()
                     Header = TranslationHelper.Get("Icon_OpenDataFolder"),
                     Command = new RelayCommand(() => Process.Start("explorer.exe", SettingHelper.LocalDataPath)),
                 },
+                _itemThemeCycle = new TrayMenuItem()
+                {
+                    Header = "Theme: Auto",
+                    Command = new RelayCommand(() =>
+                    {
+                        var current = SettingHelper.Get("AppTheme", 0, "QuickLook");
+                        var next = (current + 1) % 3;
+                        SettingHelper.Set("AppTheme", next, "QuickLook");
+                        App.SetTheme(next);
+                    }),
+                },
                 _itemAutorun = new TrayMenuItem()
                 {
                     Header = TranslationHelper.Get("Icon_RunAtStartup"),
@@ -109,6 +121,8 @@ private TrayIconManager()
         {
             _itemAutorun.IsChecked = AutoStartupHelper.IsAutorun();
             _itemCloseOnLostFocus.IsChecked = SettingHelper.Get("CloseOnLostFocus", false);
+            var theme = SettingHelper.Get("AppTheme", 0, "QuickLook");
+            _itemThemeCycle.Header = theme == 1 ? "Theme: Light" : theme == 2 ? "Theme: Dark" : "Theme: Auto";
         };
     }