Gtk.Widget::property-notify-event

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

The ::property-notify-event signal will be emitted when a property on the @widget's window has been changed or deleted.

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

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