gtk/widget_since_3_8.go
func (v *Widget) AddTickCallback(fn TickCallback, userData uintptr) int {
	tickCallbackRegistry.Lock()
	id := tickCallbackRegistry.next
	tickCallbackRegistry.next++
	tickCallbackRegistry.m[id] = tickCallbackData{fn: fn, userData: userData}
	tickCallbackRegistry.Unlock()

	return int(C._gtk_widget_add_tick_callback(v.native(), C.gpointer(uintptr(id))))
}
func (v *Widget) AddTickCallback(fn TickCallback, userData uintptr) int {
	tickCallbackRegistry.Lock()
	id := tickCallbackRegistry.next
	tickCallbackRegistry.next++
	tickCallbackRegistry.m[id] = tickCallbackData{fn: fn, userData: userData}
	tickCallbackRegistry.Unlock()

	return int(C._gtk_widget_add_tick_callback(v.native(), C.gpointer(uintptr(id))))
}
// AddTickCallback is a wrapper around gtk_widget_add_tick_callback().