16.8

第一个程序：

 1 import java.awt.Graphics;
 2 import java.awt.event.*;
 3 
 4 import javax.swing.*;
 5 
 6 public class Test_16_8 extends JFrame{
 7     private int x = 0, y = 0;
 8     
 9     public Test_16_8(){
10         JP jp1 = new JP();
11         jp1.addMouseListener(new MouseAdapter(){
12             public void mouseClicked(MouseEvent e){
13                 x = e.getX();
14                 y = e.getY();
15                 repaint();
16             }
17         });
18         add(jp1);
19     }
20     public static void main(String[] args) {
21         // TODO Auto-generated method stub
22         Test_16_8 T1 = new Test_16_8();
23         T1.setTitle("Test_16.8");
24         T1.setSize(200,200);
25         T1.setLocationRelativeTo(null);
26         T1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
27         T1.setVisible(true);
28     }
29     
30     class JP extends JPanel{
31         protected void paintComponent(Graphics g){
32             super.paintComponent(g);
33             g.drawString("("+x+","+y+")", getWidth()/2, getHeight()/2);
34         }
35     }
36 }

Test_16_8.java

效果图：

第二个程序：

 1 import java.awt.Graphics;
 2 import java.awt.event.*;
 3 
 4 import javax.swing.*;
 5 
 6 public class Test_16_8 extends JFrame{
 7     private int x = 0, y = 0;
 8     
 9     public Test_16_8(){
10         JP jp1 = new JP();
11         jp1.addMouseListener(new MouseAdapter(){
12             public void mousePressed(MouseEvent e){
13                 x = e.getX();
14                 y = e.getY();
15                 repaint();
16             }
17             public void mouseReleased(MouseEvent e){
18                 x = 0;
19                 y = 0;
20                 repaint();
21             }
22         });
23         add(jp1);
24     }
25     public static void main(String[] args) {
26         // TODO Auto-generated method stub
27         Test_16_8 T1 = new Test_16_8();
28         T1.setTitle("Test_16.8");
29         T1.setSize(200,200);
30         T1.setLocationRelativeTo(null);
31         T1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
32         T1.setVisible(true);
33     }
34     
35     class JP extends JPanel{
36         protected void paintComponent(Graphics g){
37             super.paintComponent(g);
38             g.drawString("("+x+","+y+")", getWidth()/2, getHeight()/2);
39         }
40     }
41 }

Test_16_8.java

效果图：

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