我有一个简单的乒乓球游戏，当用户点击JButton上显示的JPanel时，它应重置游戏。我怎样才能做到这一点？我想只是删除JPanel并添加一个新的（JPanel包含游戏的所有必要的代码/类引用）然而我尝试写这个，但它没有用，没什么发生。这是我的代码：
JFrame类：
public class Window extends JFrame implements ActionListener {
static int length = 1000;
static int height = 1000;
Display display = new Display();
Window() {
setTitle("Program Display");
setSize(length + 22, height + 40);
setDefaultCloseOperation(EXIT_ON_CLOSE);
JButton restart = new JButton("Start New Game");
add(display);
display.add(restart);
restart.addActionListener(this);
setVisible(true);
}
@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
remove(display);
Display display2 = new Display();
JButton restart = new JButton("Start New Game");
add(display2);
display2.add(restart);
restart.addActionListener(this);
revalidate();
repaint();
}
}
JPanel类：
public class Display extends JPanel implements ActionListener {
int up = 0;
int down = 500;
double ballx = 500;
double bally = 500;
char ballDirection;
Rectangle border;
static Rectangle borderEast;
static Rectangle borderNorth;
static Rectangle borderSouth;
static Rectangle borderWest;
static boolean gameOver;
Timer timer;
Paddle p;
Ball b;
Display() {
p = new Paddle();
b = new Ball();
up = p.up;
down = p.down;
ballx = b.ballx;
bally = b.bally;
ballDirection = b.ballDirection;
initTimer();
b.startBall();
addKeyListener(p);
setFocusable(true);
}
public void initTimer() {
timer = new Timer(10, this);
timer.start();
}
public void setUpBorders(Graphics2D g2d) {
border = new Rectangle(0, 0, Window.length, Window.height);
borderEast = new Rectangle(Window.length, 0, 2, Window.height);
borderWest = new Rectangle(0, 0, 2, Window.height);
borderSouth = new Rectangle(0, Window.height, Window.length, 2);
borderNorth = new Rectangle(0, 0, Window.length, 2);
g2d.setColor(Color.RED);
g2d.draw(border);
}
public void paintPaddle(Graphics2D g2d) {
g2d.setColor(new Color(0, 130, 130));
g2d.fill(p.paddle);
}
public void paintBall(Graphics2D g2d) {
g2d.setColor(new Color(0, 130, 130));
g2d.fillOval((int) ballx, (int) bally, 20, 20);
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
setBackground(Color.BLACK);
Graphics2D g2d = (Graphics2D) g;
setUpBorders(g2d);
paintPaddle(g2d);
paintBall(g2d);
if(gameOver == true) {
Font custom = new Font("Dialog", Font.BOLD, 60);
g2d.setColor(Color.RED);
g2d.setFont(custom);
g2d.drawString("Game Over. Your score was: " + Ball.score + "!", 50, 500);
}
}
public void checkBorderHit() {
b.checkBorderHit();
p.checkBorderHit();
}
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
up = p.up;
down = p.down;
ballx = b.ballx;
bally = b.bally;
ballDirection = b.ballDirection;
b.moveBall();
checkBorderHit();
repaint();
}
}