Gtk.Widget::leave-notify-event

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

The ::leave-notify-event will be emitted when the pointer leaves the @widget's window.

To receive this signal, the Gdk.Window associated to the widget needs to enable the #GDK_LEAVE_NOTIFY_MASK mask.

This signal will be sent to the grab widget if there is one.

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