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What are the steps of java event processing

What is an event?

An operation performed by a user on a component is called an event.

Event source: GUI component object that can generate events.

Event processing method: A method that can accept, parse and process event objects and implement interactive functions with users.

Event listener: a class that can handle events.

Steps in processing events:

Assume the event is XXXX

1. Register an event listener object for a certain event with the event source.

addXXXXListener(...);

2. Design an event listener that can handle this kind of event.

class 类名 implements XXXXListener{
重写XXXXListener接口中的方法
}

Note:

If you want to design a listener that can handle XXXX events, you only need to write a class that implements the XXXXListener interface, because in the XXXXListener interface Methods that can handle XXXX events have been defined.

eg:

import java.awt.*;
import java.awt.event.*;
class A implements ActionListener{
public void actionPerformed(ActionEvent e){//单击事件
System.out.println("haha");
}
}
public class text{
public static void main(String[] args){
Frame f=new Frame();
Button bn=new Button("ok");
f.add(bn);
A aa =new A();
bn.addActionListener(aa);
f.pack();//只显示内容高度和宽度
f.setVisible(true);
 }
}

What are the events:

ActionEvent: An event that occurs when a component is activated.

KeyEvent: Event that occurs when operating the keyboard.

MouseEvent: Occurs when the mouse is operated.

WindowsEvent: Event that occurs when operating a window.

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