Add getId method for retrieving window ID on macOS and Windows

Author: lijy91

packages/window_manager/example/lib/pages/home.dart

@@ -141,6 +141,14 @@ class _HomePageState extends State<HomePage> with TrayListener, WindowListener {
         PreferenceListSection(
           title: const Text('METHODS'),
           children: [
+            if (Platform.isWindows || Platform.isMacOS)
+              PreferenceListItem(
+                title: const Text('getId'),
+                onTap: () async {
+                  final result = await windowManager.getId();
+                  BotToast.showText(text: 'Window ID:$result');
+                },
+              ),
             PreferenceListItem(
               title: const Text('setAsFrameless'),
               onTap: () async {
@@ -180,14 +188,6 @@ class _HomePageState extends State<HomePage> with TrayListener, WindowListener {
                 print('isFocused: ${await windowManager.isFocused()}');
               },
             ),
-            if(Platform.isWindows)
-            PreferenceListItem(
-              title: const Text('getWindowHandle'),
-              onTap: () async {
-                final result = await windowManager.getWindowHandle();
-                print('HWND:$result');
-              },
-            ),
             PreferenceListItem(
               title: const Text('show / hide'),
               onTap: () async {

packages/window_manager/lib/src/window_manager.dart

@@ -104,8 +104,14 @@ class WindowManager {
     await _channel.invokeMethod('ensureInitialized');
   }
 
-  Future<int> getWindowHandle()async{
-    return await _channel.invokeMethod('getWindowHandle') as int;
+  /// Returns `int` - The ID of the window.
+  ///
+  /// For macOS, the ID is the window number.
+  /// For Windows, the ID is the window handle.
+  ///
+  /// @platforms macos,windows
+  Future<int> getId() async {
+    return await _channel.invokeMethod('getId') as int;
   }
 
   /// You can call this to remove the window frame (title bar, outline border, etc), which is basically everything except the Flutter view, also can call setTitleBarStyle(TitleBarStyle.normal) or setTitleBarStyle(TitleBarStyle.hidden) to restore it.

packages/window_manager/macos/window_manager/Sources/window_manager/WindowManager.swift

@@ -76,6 +76,10 @@ public class WindowManager: NSObject, NSWindowDelegate {
     public func waitUntilReadyToShow() {
         // nothing
     }
+
+    public func getId() -> Int {
+        return mainWindow.windowNumber
+    }
 
     public func setAsFrameless() {
         mainWindow.styleMask.insert(.fullSizeContentView)

packages/window_manager/macos/window_manager/Sources/window_manager/WindowManagerPlugin.swift

@@ -50,6 +50,9 @@ public class WindowManagerPlugin: NSObject, FlutterPlugin {
             windowManager.waitUntilReadyToShow()
             result(true)
             break
+        case "getId":
+            result(windowManager.getId())
+            break
         case "setAsFrameless":
             windowManager.setAsFrameless()
             result(true)

packages/window_manager/windows/window_manager_plugin.cpp

@@ -41,11 +41,10 @@ class WindowManagerPlugin : public flutter::Plugin {
 
  private:
   std::unique_ptr<
-    flutter::MethodChannel<flutter::EncodableValue>,
-    std::default_delete<flutter::MethodChannel<flutter::EncodableValue>>>
+      flutter::MethodChannel<flutter::EncodableValue>,
+      std::default_delete<flutter::MethodChannel<flutter::EncodableValue>>>
       channel = nullptr;
 
-
   WindowManager* window_manager;
   flutter::PluginRegistrarWindows* registrar;
 
@@ -69,8 +68,8 @@ class WindowManagerPlugin : public flutter::Plugin {
 
     // HMONITOR monitor = MonitorFromWindow(hwnd, MONITOR_DEFAULTTONEAREST);
     // Don't use `MonitorFromWindow(hwnd, MONITOR_DEFAULTTONEAREST)` above.
-    // Because if the window is restored from minimized state, the window is not in the correct monitor.
-    // The monitor is always the left-most monitor.
+    // Because if the window is restored from minimized state, the window is not
+    // in the correct monitor. The monitor is always the left-most monitor.
     // https://github.com/leanflutter/window_manager/issues/489
     HMONITOR monitor = MonitorFromRect(&sz->rgrc[0], MONITOR_DEFAULTTONEAREST);
     if (monitor != NULL) {
@@ -113,10 +112,9 @@ WindowManagerPlugin::WindowManagerPlugin(
       registrar->messenger(), "window_manager",
       &flutter::StandardMethodCodec::GetInstance());
 
-  channel->SetMethodCallHandler(
-      [this](const auto& call, auto result) {
-        HandleMethodCall(call, std::move(result));
-      });
+  channel->SetMethodCallHandler([this](const auto& call, auto result) {
+    HandleMethodCall(call, std::move(result));
+  });
 }
 
 WindowManagerPlugin::~WindowManagerPlugin() {
@@ -350,13 +348,12 @@ void WindowManagerPlugin::HandleMethodCall(
     window_manager->native_window =
         ::GetAncestor(registrar->GetView()->GetNativeWindow(), GA_ROOT);
     result->Success(flutter::EncodableValue(true));
-  }
-  else if (method_name.compare("getWindowHandle") == 0) {
-    result->Success(flutter::EncodableValue(reinterpret_cast<__int64>(window_manager->GetMainWindow())));
-  }
-  else if (method_name.compare("waitUntilReadyToShow") == 0) {
+  } else if (method_name.compare("waitUntilReadyToShow") == 0) {
     window_manager->WaitUntilReadyToShow();
     result->Success(flutter::EncodableValue(true));
+  } else if (method_name.compare("getId") == 0) {
+    result->Success(flutter::EncodableValue(
+        reinterpret_cast<__int64>(window_manager->GetMainWindow())));
   } else if (method_name.compare("setAsFrameless") == 0) {
     window_manager->SetAsFrameless();
     result->Success(flutter::EncodableValue(true));