Enable dark mode support for shell context menu #298

(Thanks to chip33 for API hint)

Config/Config.cs

@@ -9,6 +9,7 @@ namespace SystemTrayMenu
     using System.Windows;
     using System.Windows.Media;
     using Microsoft.Win32;
+    using SystemTrayMenu.DllImports;
     using SystemTrayMenu.Properties;
     using SystemTrayMenu.UserInterface.FolderBrowseDialog;
     using SystemTrayMenu.Utilities;
@@ -161,6 +162,10 @@ internal static bool IsDarkMode()
                     isDarkMode = true;
                 }
 
+                // Required for native UI rendering like the ShellContextMenu
+                NativeMethods.SetPreferredAppMode(isDarkMode ? NativeMethods.PreferredAppMode.ForceDark : NativeMethods.PreferredAppMode.ForceLight);
+                NativeMethods.FlushMenuThemes();
+
                 readDarkModeDone = true;
             }
 

NativeDllImport/Themes.cs

@@ -0,0 +1,45 @@
+// <copyright file="Themes.cs" company="PlaceholderCompany">
+// Copyright (c) PlaceholderCompany. All rights reserved.
+// </copyright>
+//
+// Copyright (c) 2023 Peter Kirmeier
+
+namespace SystemTrayMenu.DllImports
+{
+    using System.Runtime.InteropServices;
+    using System.Runtime.Versioning;
+
+    /// <summary>
+    /// See: https://gist.github.com/rounk-ctrl/b04e5622e30e0d62956870d5c22b7017
+    /// See: https://social.msdn.microsoft.com/Forums/windowsdesktop/en-US/e36eb4c0-4370-4933-943d-b6fe22677e6c/dark-mode-apis?forum=windowssdk
+    /// Wraps the method calls to native Windows DLLs.
+    /// </summary>
+    public static partial class NativeMethods
+    {
+        internal enum PreferredAppMode : int
+        {
+            Default = 0,
+            AllowDark = 1,
+            ForceDark = 2,
+            ForceLight = 3,
+        }
+
+        /// <summary>
+        /// No official documentation.
+        /// Seems to set mode that the UI shall use for rendering UI elements.
+        /// </summary>
+        /// <param name="preferredAppMode">Desired mode.</param>
+        /// <returns>Undocumented.</returns>
+        [SupportedOSPlatform("windows")]
+        [DllImport("uxtheme.dll", EntryPoint = "#135", SetLastError = true, CharSet = CharSet.Unicode, CallingConvention = CallingConvention.Winapi)]
+        internal static extern int SetPreferredAppMode(PreferredAppMode preferredAppMode);
+
+        /// <summary>
+        /// No official documentation.
+        /// Seems to switch UI mode which was set by SetPreferredAppMode.
+        /// </summary>
+        [SupportedOSPlatform("windows")]
+        [DllImport("uxtheme.dll", EntryPoint = "#136", SetLastError = true, CharSet = CharSet.Unicode, CallingConvention = CallingConvention.Winapi)]
+        internal static extern void FlushMenuThemes();
+    }
+}

README.md

@@ -269,7 +269,7 @@ Thanks for ideas, reporting issues and contributing!
 #285 #286 [dao-net](https://github.com/dao-net),
 #288 William P.,
 #294 #295 #296 Stefan M.,
-#225 #297 #299 #317 #321 #324 #330 #386 #390 #401 #402 #407 #409 #414 #416 #418 #428 #430 #443 [chip33](https://github.com/chip33),
+#225 #297 #298 #299 #317 #321 #324 #330 #386 #390 #401 #402 #407 #409 #414 #416 #418 #428 #430 #443 [chip33](https://github.com/chip33),
 #298 [phanirithvij](https://github.com/phanirithvij),
 #306 [wini2](https://github.com/wini2),
 #370 [dna5589](https://github.com/dna5589),