fix: synchronize macOS window theme on flutter theme changed.

flutter/lib/common.dart

@@ -9,6 +9,7 @@ import 'package:back_button_interceptor/back_button_interceptor.dart';
 import 'package:desktop_multi_window/desktop_multi_window.dart';
 import 'package:ffi/ffi.dart';
 import 'package:flutter/foundation.dart';
+import 'package:flutter_hbb/utils/platform_channel.dart';
 import 'package:win32/win32.dart' as win32;
 import 'package:flutter/gestures.dart';
 import 'package:flutter/material.dart';
@@ -235,6 +236,12 @@ class MyTheme {
       }
       bind.mainChangeTheme(dark: mode.toShortString());
     }
+    // Synchronize the window theme of the system.
+    if (Platform.isMacOS) {
+      final isDark = mode == ThemeMode.dark;
+      RdPlatformChannel.instance.changeSystemWindowTheme(
+          isDark ? SystemWindowTheme.dark : SystemWindowTheme.light);
+    }
   }
 
   static ThemeMode currentThemeMode() {
@@ -1686,3 +1693,16 @@ String getWindowName({WindowType? overrideType}) {
 String getWindowNameWithId(String id, {WindowType? overrideType}) {
   return "${DesktopTab.labelGetterAlias(id).value} - ${getWindowName(overrideType: overrideType)}";
 }
+
+void updateSystemWindowTheme() {
+  // Set system window theme for macOS
+  final userPreference = MyTheme.getThemeModePreference();
+  if (userPreference != ThemeMode.system) {
+    if (Platform.isMacOS) {
+      RdPlatformChannel.instance.changeSystemWindowTheme(
+          userPreference == ThemeMode.light
+              ? SystemWindowTheme.light
+              : SystemWindowTheme.dark);
+    }
+  }
+}

flutter/lib/desktop/widgets/refresh_wrapper.dart

@@ -1,9 +1,11 @@
 import 'package:flutter/material.dart';
+import 'package:flutter_hbb/common.dart';
 import 'package:flutter_hbb/main.dart';
 import 'package:get/get.dart';
 
 class RefreshWrapper extends StatefulWidget {
   final Widget Function(BuildContext context) builder;
+
   const RefreshWrapper({super.key, required this.builder});
 
   @override
@@ -30,6 +32,8 @@ class RefreshWrapperState extends State<RefreshWrapper> {
     if (Get.context != null) {
       (context as Element).visitChildren(_rebuildElement);
     }
+    // Synchronize the window theme of the system.
+    updateSystemWindowTheme();
     setState(() {});
   }
 

flutter/lib/main.dart

@@ -108,6 +108,8 @@ Future<void> initEnv(String appType) async {
   await initGlobalFFI();
   // await Firebase.initializeApp();
   _registerEventHandler();
+  // Update the system theme.
+  updateSystemWindowTheme();
 }
 
 void runMainApp(bool startService) async {
@@ -327,6 +329,8 @@ class _AppState extends State<App> {
         to = ThemeMode.light;
       }
       Get.changeThemeMode(to);
+      // Synchronize the window theme of the system.
+      updateSystemWindowTheme();
       if (desktopType == DesktopType.main) {
         bind.mainChangeTheme(dark: to.toShortString());
       }

flutter/lib/utils/platform_channel.dart

@@ -0,0 +1,34 @@
+import 'dart:io';
+
+import 'package:flutter/foundation.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_hbb/main.dart';
+
+enum SystemWindowTheme { light, dark }
+
+/// The platform channel for RustDesk
+class RdPlatformChannel {
+  RdPlatformChannel._();
+
+  static final RdPlatformChannel _windowUtil = RdPlatformChannel._();
+
+  static RdPlatformChannel get instance => _windowUtil;
+
+  final MethodChannel _osxMethodChannel =
+      MethodChannel("org.rustdesk.rustdesk/macos");
+  final MethodChannel _winMethodChannel =
+      MethodChannel("org.rustdesk.rustdesk/windows");
+  final MethodChannel _linuxMethodChannel =
+      MethodChannel("org.rustdesk.rustdesk/linux");
+
+  /// Change the theme of the system window
+  Future<void> changeSystemWindowTheme(SystemWindowTheme theme) {
+    assert(Platform.isMacOS);
+    if (kDebugMode) {
+      print(
+          "[Window ${kWindowId ?? 'Main'}] change system window theme to ${theme.name}");
+    }
+    return _osxMethodChannel
+        .invokeMethod("setWindowTheme", {"themeName": theme.name});
+  }
+}