事件处理

package ck;
import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class chuangkou implements ActionListener{
  JFrame chuangkou;
  JPanel m;
  JButton a;
  JLabel c;
public chuangkou() {
   chuangkou=new JFrame("事件处理练习窗口");
   a=new JButton("改变");
  m=new JPanel();
  c=new JLabel("单击");
  a.addActionListener(this);
  a.setBounds(40,60,80,60);  
  m.add(a);
  m.add(c);
  chuangkou.add(m);
  chuangkou.setVisible(true);
  chuangkou.setSize(500,600);
}
public void actionPerformed(ActionEvent e) {
    m.setBackground(Color.blue);
    
    
}
public static void main(String[]args) {
    new chuangkou();
}
}