Proposal: system menu

[jpnurmi]

Could there be API to show the window system menu on Linux and Windows?

• https://docs.gtk.org/gdk3/method.Window.show_window_menu.html
• https://docs.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-getsystemmenu

[lijy91]

I tried adding this functionality for the windows platform, but it doesn't seem to display the state of the menu items correctly

[jpnurmi]

Strange, the docs claim that it should be automatically taken care of. Which state is wrong?

The system automatically grays items on the standard window menu, depending on the situation. The application can perform its own checking or graying by responding to the WM_INITMENU message that is sent before any menu is displayed.

[lijy91]

I've added a popUpWindowMenu method for windows and linux platforms, but I can't fix this incorrect state on Windows for now.

[jpnurmi]

Awesome, thanks!

I gave it a very quick try with minimal test app:

import 'package:flutter/material.dart';
import 'package:window_manager/window_manager.dart';

Future<void> main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await windowManager.ensureInitialized();

  runApp(
    MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: const Text('window_manager')),
        body: GestureDetector(
          onSecondaryTapDown: (details) {
            // print(details.globalPosition);
            windowManager.popUpWindowMenu();
          },
        ),
      ),
    ),
  );
}

On Ubuntu 22.04 + Wayland, the menu appears but some assertions fail:

(flutter_application_13:343404): GLib-GObject-CRITICAL **: 13:58:06.740: g_object_get: assertion 'G_IS_OBJECT (object)' failed
(flutter_application_13:343404): Gdk-CRITICAL **: 13:58:06.740: gdk_device_get_seat: assertion 'GDK_IS_DEVICE (device)' failed
(flutter_application_13:343404): Gdk-CRITICAL **: 13:58:06.740: gdk_seat_ungrab: assertion 'GDK_IS_SEAT (seat)' failed

[lijy91]

I'm not very familiar with linux, do you know what causes these to appear?

[jpnurmi]

Interesting, the warnings were actually from the X11 backend because VS Code sets GDK_BACKEND=x11. The Wayland backend would crash due to missing device, but both are fixed by #145.