[windows] Implement getTitleBarHeight methods #34

Author: lijy91

example/lib/pages/home.dart

@@ -423,6 +423,15 @@ class _HomePageState extends State<HomePage> with WindowListener {
               ),
               onTap: () {},
             ),
+            PreferenceListItem(
+              title: Text('getTitleBarHeight'),
+              onTap: () async {
+                int titleBarHeight = await windowManager.getTitleBarHeight();
+                BotToast.showText(
+                  text: 'titleBarHeight: $titleBarHeight',
+                );
+              },
+            ),
             PreferenceListItem(
               title: Text('setSkipTaskbar'),
               onTap: () async {

lib/src/window_manager.dart

@@ -328,6 +328,10 @@ class WindowManager {
     await _channel.invokeMethod('setTitleBarStyle', arguments);
   }
 
+  Future<int> getTitleBarHeight() async {
+    return await _channel.invokeMethod('getTitleBarHeight');
+  }
+
   /// Makes the window not show in the taskbar / dock.
   Future<void> setSkipTaskbar(bool isSkipTaskbar) async {
     final Map<String, dynamic> arguments = {

windows/window_manager.cpp

@@ -79,6 +79,7 @@ class WindowManager
     std::string WindowManager::GetTitle();
     void WindowManager::SetTitle(const flutter::EncodableMap &args);
     void WindowManager::SetTitleBarStyle(const flutter::EncodableMap &args);
+    int WindowManager::GetTitleBarHeight();
     void WindowManager::SetSkipTaskbar(const flutter::EncodableMap &args);
     bool WindowManager::HasShadow();
     void WindowManager::SetHasShadow(const flutter::EncodableMap &args);
@@ -532,6 +533,19 @@ void WindowManager::SetTitleBarStyle(const flutter::EncodableMap &args)
                  SWP_NOZORDER | SWP_NOOWNERZORDER | SWP_NOMOVE | SWP_NOSIZE | SWP_FRAMECHANGED);
 }
 
+int WindowManager::GetTitleBarHeight()
+{
+    HWND hWnd = GetMainWindow();
+
+    TITLEBARINFOEX *ptinfo = (TITLEBARINFOEX *)malloc(sizeof(TITLEBARINFOEX));
+    ptinfo->cbSize = sizeof(TITLEBARINFOEX);
+    SendMessage(hWnd, WM_GETTITLEBARINFOEX, 0, (LPARAM)ptinfo);
+    int height = ptinfo->rcTitleBar.bottom - ptinfo->rcTitleBar.top;
+    free(ptinfo);
+
+    return height;
+}
+
 void WindowManager::SetSkipTaskbar(const flutter::EncodableMap &args)
 {
     bool is_skip_taskbar = std::get<bool>(args.at(flutter::EncodableValue("isSkipTaskbar")));

windows/window_manager_plugin.cpp

@@ -413,6 +413,12 @@ void WindowManagerPlugin::HandleMethodCall(const flutter::MethodCall<flutter::En
         window_manager->SetTitleBarStyle(args);
         result->Success(flutter::EncodableValue(true));
     }
+    else if (method_name.compare("getTitleBarHeight") == 0)
+    {
+        int value = window_manager->GetTitleBarHeight();
+        result->Success(flutter::EncodableValue(value));
+    }
+
     else if (method_name.compare("setSkipTaskbar") == 0)
     {
         const flutter::EncodableMap &args = std::get<flutter::EncodableMap>(*method_call.arguments());