一个java小程序,applet,一直感觉代码没问题,编译通过,可就是不能运行...

发布网友发布时间：2024-09-27 08:49

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共4个回答

热心网友时间：2024-09-28 20:11

repaint();这个是重绘就是重新绘制现在的界面,调用后由系统自己完成

热心网友时间：2024-09-28 20:07

发不上来，到这边看看：
http://hi.baidu.com/top_beidu/blog/item/f0240badcbdefeec1f17a20a.html

热心网友时间：2024-09-28 20:05

加个主函数测试一下

热心网友时间：2024-09-28 20:05

我有一个代码虽然不是光的折射可是也实现了小球碰倒边缘就会弹回来的源码
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.util.*;
import javax.swing.*;

public class BounceThread
{
public static void main(String[] args)
{
JFrame frame = new BounceFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}

class BallRunnable implements Runnable
{

public BallRunnable (Ball aBall, Component aComponent)
{
ball = aBall;
component = aComponent;
}

public void run()
{
try
{
for (int i = 1; i <= STEPS; i++)
{
ball.move(component.getBounds());
component.repaint();
Thread.sleep(DELAY);
}
}
catch (InterruptedException e)
{
}
}

private Ball ball;
private Component component;
public static final int STEPS = 1000;
public static final int DELAY = 4;
}

class Ball
{
//这块就是碰到边缘就弹回来的地方的坐标
public void move(Rectangle2D bounds)
{

y += dy;
x +=dx;
if (x < bounds.getMinX())
{
x = bounds.getMinX();
dx = -dx;
}
if (x + XSIZE >= bounds.getMaxX())
{
x = bounds.getMaxX() - XSIZE;
dx = -dx;
}
if (y < bounds.getMinY())
{
y = bounds.getMinY();
dy = -dy;
}
if (y + YSIZE >= bounds.getMaxY())
{
y = bounds.getMaxY() - YSIZE;
dy = -dy;
}
}

public Ellipse2D getShape()
{
return new Ellipse2D.Double(x, y, XSIZE, YSIZE);
}

private static final int XSIZE = 15;
private static final int YSIZE = 15;
private double x = 0;
private double y = 0;
private double dx = 10;
private double dy = 100;
}

class BallPanel extends JPanel
{

public void add(Ball b)
{
balls.add(b);
}

public void paintComponent(Graphics g)
{
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
for (Ball b : balls)
{
g2.fill(b.getShape());
}
}

private ArrayList<Ball> balls = new ArrayList<Ball>();
}

class BounceFrame extends JFrame
{

public BounceFrame()
{
setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
setTitle("BounceThread");

panel = new BallPanel();
add(panel, BorderLayout.CENTER);
JPanel buttonPanel = new JPanel();
addButton(buttonPanel, "Start",new ActionListener()});
addButton(buttonPanel, "Close",new ActionListener() });
add (buttonPanel, BorderLayout.SOUTH);
}

public void addButton(Container c, String title, ActionListener listener)
{
JButton button = new JButton(title);
c.add(button);
button.addActionListener(listener);
}

public void addBall()
{
Ball b = new Ball();
panel.add(b);
Runnable r = new BallRunnable(b, panel);
Thread t = new Thread(r);
t.start();
}

private BallPanel panel;
public static final int DEFAULT_WIDTH = 4500;
public static final int DEFAULT_HEIGHT = 3500;
public static final int STEPS = 1000;
public static final int DELAY = 5;
}

稍加修改你的源码就会实现
为了学好编程我希望你自己动手我已经把饭送入你嘴里了不用我来嚼吧
请参考