AWT09-弹球小游戏

1.补充

　　为了让Java绘制动画，可以借助Swing的定时器，其构造为：

方法名	说明
Timer(int delay,ActionListener listener)	每间隔delay毫秒，自动触发ActionListener里的事件处理

　　

  1 import javax.swing.*;
  2 import java.awt.*;
  3 import java.awt.event.*;
  4
  5 public class ballGameDemo {
  6     private final int TABLE_WIDTH = 300;
  7     private final int TABLE_HEIGHT = 400;
  8
  9     private final int r_width = 60;
 10     private final int r_height = 20;
 11
 12     private final int ball_size = 16;
 13
 14     private int ballx = 120;
 15     private int bally = 20;
 16
 17     private int speedX = 5;
 18     private int speedY = 5;
 19
 20     private int r_x = 120;
 21     private final int r_y = 340;
 22
 23     private boolean isOver = false;
 24
 25     private Timer time;
 26
 27     private class MyCanvas extends Canvas {
 28         @Override
 29         public void paint(Graphics g){
 30             if (isOver){
 31                 g.setColor(Color.RED);
 32                 g.setFont(new Font("Times",Font.BOLD,30));
 33                 g.drawString("Game Over",80,200);
 34             }else{
 35                 g.setColor(Color.BLUE);
 36                 g.fillOval(ballx,bally,ball_size,ball_size);
 37                 g.drawOval(ballx,bally,ball_size,ball_size);
 38
 39                 g.setColor(Color.PINK);
 40                 g.fillRect(r_x,r_y,r_width,r_height);
 41                 g.drawRect(r_x,r_y,r_width,r_height);
 42             }
 43         }
 44     }
 45
 46     Frame frame = new Frame("弹弹球");
 47
 48     MyCanvas canvas = new MyCanvas();
 49
 50
 51
 52
 53     public void init() {
 54         KeyListener keyListener = new KeyAdapter() {
 55             @Override
 56             public void keyPressed(KeyEvent e) {
 57                 int keyCode = e.getKeyCode();
 58
 59                 if (keyCode == KeyEvent.VK_A){
 60                     if (r_x > 0){
 61                         r_x -= 15;
 62                     }
 63                 }
 64
 65                 if (keyCode == KeyEvent.VK_D){
 66                     if (r_x < (TABLE_WIDTH - r_width)){
 67                         r_x +=15;
 68                     }
 69                 }
 70             }
 71         };
 72
 73         frame.addKeyListener(keyListener);
 74         canvas.addKeyListener(keyListener);
 75
 76         ActionListener actionListener = new ActionListener() {
 77             @Override
 78             public void actionPerformed(ActionEvent e) {
 79                 if (ballx <= 0 || ballx > (TABLE_WIDTH - ball_size)){
 80                     speedX = -speedX;
 81                 }
 82
 83                 if (bally <= 0 ||(ballx > (r_y - ball_size) && ballx > r_x && ballx < (r_x+r_width))){
 84                     speedY = -speedY;
 85                 }
 86
 87                 if (bally > (r_y-ball_size) && (ballx < r_x || ballx >(r_x+r_width))){
 88                     time.stop();
 89                     isOver = true;
 90                     canvas.repaint();
 91                 }
 92
 93                 ballx += speedX;
 94                 bally += speedY;
 95
 96                 canvas.repaint();
 97             }
 98         };
 99         time = new Timer(10, actionListener);
100         time.start();
101
102         canvas.setPreferredSize(new Dimension(TABLE_WIDTH,TABLE_HEIGHT));
103         frame.add(canvas);
104
105         frame.addWindowListener(new WindowAdapter() {
106             @Override
107             public void windowClosing(WindowEvent e) {
108                 System.exit(0);
109             }
110         });
111         frame.pack();
112         frame.setVisible(true);
113     }
114
115     public static void main(String[] args) {
116         new ballGameDemo().init();
117     }
118 }