java学习笔记_GUI(4)

 1 import javax.swing.*;
 2 import java.awt.event.*;
 3 import java.awt.*;
 4 
 5 class MyPanel_0 extends JPanel {
 6     public void paintComponent( Graphics g ) {
 7         g.setColor( Color.orange );
 8         g.fillRect(20, 50, 100, 100);
 9     }
10 }
11 
12 class MyPanel_1 extends JPanel {
13     public void paintComponent( Graphics g ) {
14         Image image = new ImageIcon("Winter.jpg").getImage();
15         g.drawImage(image, 3, 4, this);
16     }
17 }
18 
19 class MyPanel_2 extends JPanel {
20     public void paintComponent( Graphics g ) {
21         g.fillRect(0, 0, this.getWidth(), this.getHeight());
22         int red = (int) (Math.random() * 255);
23         int green = (int) (Math.random() * 255);
24         int blue = (int) (Math.random() * 255);
25         Color randomColor = new Color(red, green, blue);
26         g.setColor(randomColor);
27         g.fillOval(70, 40, 100, 100);
28     }
29 }
30 
31 class MyPanel_3 extends JPanel {
32     public void paintComponent( Graphics g ) {
33         Graphics2D g2d = (Graphics2D) g;
34         GradientPaint gradient = new GradientPaint(70, 70, Color.blue, 150, 150, Color.orange);
35         g2d.setPaint( gradient );
36         g2d.fillOval(70, 70, 100, 100);
37     }
38 }
39 
40 class Gui implements ActionListener{
41     
42     JButton button = new JButton("click me");
43     JFrame frame = new JFrame();
44     
45     private void set_frame() {
46         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
47         frame.setSize(300, 200);
48         frame.setVisible(true);
49     }
50 
51     public void show_button() {
52         set_frame();
53         frame.getContentPane().add(button);
54         button.addActionListener(this);
55     }
56     
57     public void show_my_panel( String index) {
58         set_frame();
59         if ( index.equals("0") ) {
60             frame.getContentPane().add(new MyPanel_0());
61         }
62         else if ( index.equals("1") ) {
63             frame.getContentPane().add(new MyPanel_1());
64         }
65         else if ( index.equals("2") ) {
66             frame.getContentPane().add(new MyPanel_2());
67         }
68         else if ( index.equals("3") ) {
69             frame.getContentPane().add(new MyPanel_3());
70         }
71     }
72     
73     public void actionPerformed( ActionEvent event ) {
74         button.setText("I‘ve been clicked!");
75     }
76 }
77 
78 class GuiTest {
79     public static void main( String[] args ) {
80         Gui gui = new Gui();
81         if ( args.length > 0 ) {
82             gui.show_my_panel( args[0] );
83         }
84         else {
85             gui.show_button();
86         }
87     }
88 }