如何注册控件与取消控件注册。
How to register with the removal of the control register controls.
为此，我们为每一类型控件使用了一组注册函数：按钮、标签等等。
For this we use a set of register functions for each type of widget: buttons, labels, and so on.
然后发生该事件的通知会发送给控件中为该事件类型注册的所有监听器，发送顺序是这些监听器在控件上的注册顺序。
This is followed by notification of event occurrence to all listeners of the widget registered for that same event type and in the order in which the listeners were registered on widget.
应用推荐