event listener Interface

No Listener interface is used; instead attributes that match the interesting event handler entry points defined by the class (for example, actionPerformed) are set to Jython functions.

没有使用 Listener接口，而是使用该类定义的匹配要注意的事件处理程序入口点的特性（例如 actionPerformed）设置给 Jython 函数。

According to the requirements of the model, listener class and it's object will be created to register to the event source and realize the specific method in interface.

根据模型要求，要创建监听器类及其对象，完成向事件源的注册并实现接口中的特定方法。