Gtk.Widget::grab-broken-event

function callback(widget, event:Gdk.EventGrabBroken, ):Boolean;

Emitted when a pointer or keyboard grab on a window belonging to @widget gets broken.

On X11, this happens when the grab window becomes unviewable (i.e. it or one of its ancestors is unmapped), or if the same application grabs the pointer or keyboard again.

Since 2.8

widget: instance of Gtk.Widget that is emitting the signal
event: the Gdk.EventGrabBroken event
Returns: true to stop other handlers from being invoked for the event. false to propagate the event further.