func (w *Window) AddList(x, y, width, height int) *List {
	// we can ignore error for builtins
	l, _ := w.AddWidget(WidgetList, x, y)
	list := l.(*List)
	list.width = width
	list.height = height
	list.Resize()
	list.SetAttributes(defaultAttributes())

	list.content = make([]string, 0, 1000)
	return list
}
func (w *Window) AddList(x, y, width, height int) *List {
	// we can ignore error for builtins
	l, _ := w.AddWidget(WidgetList, x, y)
	list := l.(*List)
	list.width = width
	list.height = height
	list.Resize()
	list.SetAttributes(defaultAttributes())

	list.content = make([]string, 0, 1000)
	return list
}
// AddList is a convenience function to add a new list to a window.  It wraps
// the AddWidget call.  AddList must be called from queue.