1 package LHB.inherit; 2 import javax.swing.*; 3 import java.awt.*; 4 import java.awt.event.ActionEvent; 5 import java.awt.event.ActionListener; 6 public class Windows implements ActionListener 7 { 8     JFrame f; 9     JPanel p;10     JLabel a1,a2;11     JTextField c1,c2;12     JButton b1,b2;13     public Windows()14     {15         f=new JFrame("登陆");16         p=new JPanel();17         a1=new JLabel("用户名：");18         a2=new JLabel("   口令：");19         b1=new JButton("确定");20         b2=new JButton("取消");21         c1=new JTextField(5);22         c2=new JTextField(5);23         f.setVisible(true);24         f.setSize(180,150);25         b1.addActionListener((ActionListener) this);26         p.add(a1);27         p.add(c1);28         p.add(a2);29         p.add(c2);30         p.add(b1);31         p.add(b2);32         f.add(p);33     }34     public void actionPerformed(ActionEvent e) 35     {36             p.setBackground(Color.blue);37         }38     public static void main(String[] args) 39     {40         new Windows();41     }42 43 }