事件处理。

package kl;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class EventDemo {
    Frame frame=new Frame("这里测试事件处理");
    TextField tf=new TextField(30);

    Button ok=new Button("确认");

    public void init(){
        MyListener myListener=new MyListener();

        ok.addActionListener(myListener);

        frame.add(tf,BorderLayout.NORTH);
        frame.add(ok);

        frame.pack();
        frame.setVisible(true);
    }

    private class MyListener implements ActionListener{

        @Override
        public void actionPerformed(ActionEvent e) {
            tf.setText("Helllo World");
        }
    }
    public static void main(String[] args) {
        new EventDemo().init();
    }
}