Re: [gtk-list] Bug in Toggle Button {Was: problem with threads and toggle button]

[Damon Chaplin <damon karuna freeserve co uk>]

Ionutz Borcoman wrote:
> 
> Ionutz Borcoman wrote:
> >
> > if( form->_pause->Widget() == gtk_grab_get_current())
> >   gtk_grab_remove(form->_pause->Widget());
> > But this makes me believe that there is a problem in
> > gdk_threads_enter() or in the design of the toggle.
> 
> Hi,
> 
> This was not enough. Though it removed the lock, it made the button act
> strange when enabled, because it button_down was scrued. The complete
> solution (for my case) is like this:
> 
>         GtkButton *btn = GTK_BUTTON(form->_pause->Widget());
>         if( GTK_WIDGET(btn)  == gtk_grab_get_current()){
>           gtk_grab_remove( GTK_WIDGET(btn) );
>           if( btn->button_down )
>                 btn->button_down = ! btn->button_down;
>         }
> 
> Now I think that the problem is more in the ToggleButton than in the
> gdk_thread_enter. And I believe the button should check if it needs to
> release the grabb when it is disabled and return to its previous state
> (act like the user has released the mouse outside the button's area, to
> cancel its action.) I didn't check other buttons, but I think all
> buttons should behave this way. Please correct me if I'm wrong.

I think the problem is partly caused by GTK+ not passing some GDK events on to
widgets which are insensitive. (See gtk_propagate_event() in gtk/gtkmain.c)

So if you are pressing a button, and it is set insensitive from another
thread, then it won't receive the button release event. So it won't release
the grab, and it may be in a bit of a weird state internally.

Is GTK+ supposed to be thread-safe?

Damon