Constant for back/forward mouse buttons

[d47081]

Can I use any constants from the gtk-rs assets for these static digits (0, 8, 9) as the button values?

application_window.add_controller({
    use gtk::prelude::GestureSingleExt;
    let button_controller = gtk::GestureClick::builder().button(0).build(); // <-
    button_controller.connect_pressed({
        let window = window.clone();
        move |this, _, _, _| match this.current_button() {
            8 => window.tab.history_back(None), // <-
            9 => window.tab.history_forward(None), // <-
            _ => {}
        }
    });
    button_controller
});

[bilelmoussaoui]

gdk only exposes the following buttons https://github.com/gtk-rs/gtk4-rs/blob/main/gdk4/sys/src/lib.rs#L303-L305