On 17 April 2015 at 16:15, Carlos Garnacho <carl...@gnome.org> wrote: > Hey Michal, > > On Fri, Apr 17, 2015 at 2:47 PM, Michal Suchanek <hramr...@gmail.com> wrote: > <snip> > >>> In the X11 world, this would roughly be a Virtual Core >>> Pointer+Keyboard grab (not that touch and active grabs are trouble >>> free in X11, but...), GTK+ for example does grab both devices on every >>> of those grabbing places wayland/xdg protocols are trying to cater for >>> (I've even pondered about adding a gdk_device_grab_pair() for years). >>> >>> I think some consistent model should be devised here, and embedded >>> into the protocol (docs). >>> >> >> The serious problem with X11 grabs is that they are completely >> independent of the event that triggered them and can only be released >> by the application that started them. >> >> So it happens that an application that gets stuck due to code error or >> is running in a debugger at the time a grab is active never releases >> the grab which >> >> 1) prevents other applications from receiving input >> 2) prevents further grabs >> >> It might be worth considering if there is generic enough drag semantic >> that the grab could be handled in compositor outside of application >> code, even with click-lock and whatnot. > > Nothing prevents wayland compositors today from undoing grabs when > clients get destroyed, or surfaces don't respond to pings. Affecting > this proposal, the pointer should re-enter the surface underneath and > keyboard focus restablished after the grab is "broken".
Nothing prevents the X server either. It hopefully breaks the grabs initiated by clients when they are destroyed, too. However, there is no mechanism for breaking a grab of a client other than destroying it *and* destroying the client cannot be done from within the X session because it is grabbed. Thanks Michal _______________________________________________ wayland-devel mailing list wayland-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/wayland-devel
