Expose .with_class() in WindowDescriptor after new winit release to allow setting window class on X11 and app_id on Wayland.

[heavyrain266]

What problem does this solve or what need does it fill?

Field .with_app_id() is used to set App's ID to be accessed by Compositor to e.g. set specific rules for given window or group of windows under same id, for example enabling/disabling server-side opacity, disabling CSD, hardcoding tag/workspace on startup, setting position etc.

What solution would you like?

use bevy::prelude::*;

fn main() {
    App::new()
        .insert_resource(
            WindowDescriptor {
                title: "Game Title".into(),
                // Value should be not have spaces, can be e.g. org.bevy.gameTitle (like in GTK) or anything else.
                app_id: "game_title".into(),
            
               ..Default::default()
            }
        )
        .run();
}

What alternative(s) have you considered?

None.

Additional context

For now, every bevy game have app_id exposed as <NULL>, there are programs like lswt or waylevel for querying info about connected clients and their app_id, programs like that may not work under KDE/GNOME if they don't implement protocols which allow clients to query such info from Compositor.

[mockersf]

relevant winit api: https://docs.rs/winit/latest/winit/window/struct.WindowBuilder.html#method.with_app_id. This should be feature gated on wayland

[bjorn3]

Why should it be feature gated on wayland? It would be much easier to allow it on all platforms and just pass it to winit on unix. In addition while winit currently only uses it on wayland, other OSes do have a similar concept. For example macOS has the bundle id. And gtk has an application id that is used for wayland and for remote control using dbus. In addition things like the RegisterClient method of the org.Xfce.Session.Manager dbus interface also require an app id for session management.

[mockersf]

Maybe, but the method is written as working only on wayland. Otherwise we should expose the canvas option on all platforms too I guess.

[heavyrain266]

Why should it be feature gated on wayland? It would be much easier to allow it on all platforms and just pass it to winit on unix. In addition while winit currently only uses it on wayland, other OSes do have a similar concept. For example macOS has the bundle id. And gtk has an application id that is used for wayland and for remote control using dbus. In addition things like the RegisterClient method of the org.Xfce.Session.Manager dbus interface also require an app id for session management.

I don't really know how other systems handle that kind of feature, I'm not really interested in GTK because it does everything in weird way just like GNOME itself, X11 doesn't even have any documentation other than XML file with general implementation, as well as Xorg's 400k lines of code.

[heavyrain266]

Future winit release will include unified .with_class method which is used to set window class on X11 and app_id on Wayland. We should expose that one instead.

[kchibisov]

New winit will have unified call with_name on unix to set class/app_id.