Fatal编程技术网
  • java/
  • Java 如何在JPanel中设置矩形动画？

Java 如何在JPanel中设置矩形动画？

java swing user-interface

Java 如何在JPanel中设置矩形动画？,java,swing,user-interface,jframe,jpanel,Java,Swing,User Interface,Jframe,Jpanel,我想为我的项目学习一些关于JAVA的技巧 我想设置矩形leftoright和righttoleft的动画，但我无法将相同的函数应用于球动画 此外，如何以y坐标为边界在不同的x方向开始我的球 非常感谢你的建议和帮助 我的代码： import javax.swing.Timer; import java.util.ArrayList; import java.awt.*; import javax.swing.*; import java.awt.event.*; public class Mu

我想为我的项目学习一些关于JAVA的技巧

我想设置矩形leftoright和righttoleft的动画，但我无法将相同的函数应用于球动画

此外，如何以y坐标为边界在不同的x方向开始我的球

非常感谢你的建议和帮助

我的代码：

import javax.swing.Timer;
import java.util.ArrayList;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;

public class MultipleBall extends JApplet {
public MultipleBall() {
    add(new BallControl());
}

class BallControl extends JPanel {
    private BallPanel ballPanel = new BallPanel();
    private JButton Suspend = new JButton("Suspend");
    private JButton Resume = new JButton("Resume");
    private JButton Add = new JButton("+1");
    private JButton Subtract = new JButton("-1");
    private JScrollBar Delay = new JScrollBar();

    public BallControl() {
        // Group buttons in a panel
        JPanel panel = new JPanel();
        panel.add(Suspend);
        panel.add(Resume);
        panel.add(Add);
        panel.add(Subtract);

        // Add ball and buttons to the panel
        ballPanel.setBorder(new javax.swing.border.LineBorder(Color.red));
        Delay.setOrientation(JScrollBar.HORIZONTAL);
        ballPanel.setDelay(Delay.getMaximum());
        setLayout(new BorderLayout());
        add(Delay, BorderLayout.NORTH);
        add(ballPanel, BorderLayout.CENTER);
        add(panel, BorderLayout.SOUTH);

        // Register listeners
        Suspend.addActionListener(new Listener());
        Resume.addActionListener(new Listener());
        Add.addActionListener(new Listener());
        Subtract.addActionListener(new Listener());
        Delay.addAdjustmentListener(new AdjustmentListener() {

            public void adjustmentValueChanged(AdjustmentEvent e) {
                ballPanel.setDelay(Delay.getMaximum() - e.getValue());
            }
        });
    }

    class Listener implements ActionListener {

        public void actionPerformed(ActionEvent e) {
            if (e.getSource() == Suspend)
                ballPanel.suspend();
            else if (e.getSource() == Resume)
                ballPanel.resume();
            else if (e.getSource() == Add)
                ballPanel.add();
            else if (e.getSource() == Subtract)
                ballPanel.subtract();
        }
    }
}

class BallPanel extends JPanel {
    private int delay = 30;
    private ArrayList<Ball> list = new ArrayList<Ball>();

    // Create a timer with the initial delay
    protected Timer timer = new Timer(delay, new ActionListener() {
        /** Handle the action event */
        public void actionPerformed(ActionEvent e) {
            repaint();
        }
    });

    public BallPanel() {
        timer.start();
    }

    public void add() {
        list.add(new Ball());
    }

    public void subtract() {
        if (list.size() > 0)
            list.remove(list.size() - 1); // Remove the last ball
    }

    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        g.drawRect(185, 279, 50, 15);
        g.setColor(Color.RED);
        g.fillRect(185, 279, 50, 15);

        for (int i = 0; i < list.size(); i++) {
            Ball ball = (Ball) list.get(i); // Get a ball
            g.setColor(ball.color); // Set ball color

            // Check boundaries
            if (ball.x < 0 || ball.x > getWidth())
                ball.dx = -ball.dx;

            if (ball.y < 0 || ball.y > getHeight())
                ball.dy = -ball.dy;

            // Adjust ball position
            ball.x += ball.dx;
            // ball.y += ball.dy;
            g.fillOval(ball.x - ball.radius, ball.y - ball.radius,
                    ball.radius * 2, ball.radius * 2);
        }
    }

    public void suspend() {
        timer.stop();
    }

    public void resume() {
        timer.start();
    }

    public void setDelay(int delay) {
        this.delay = delay;
        timer.setDelay(delay);
    }
}

class Ball {
    int x = 20;
    int y = 20; // Current ball position
    int dx = 2; // Increment on ball's x-coordinate
    int dy = 2; // Increment on ball's y-coordinate
    int radius = 15; // Ball radius
    Color color = new Color((int) (Math.random() * 256),
            (int) (Math.random() * 256), (int) (Math.random() * 256));
}

/** Main method */
public static void main(String[] args) {
    JFrame frame = new JFrame();
    JApplet applet = new MultipleBallApp();
    frame.add(applet);
    frame.setTitle("MultipleBallApp");
    frame.setLocationRelativeTo(null); // Center the frame
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setSize(400, 400);
    frame.setLocationRelativeTo(null); // Center the frame
    frame.setVisible(true);
}
}

导入javax.swing.Timer；
导入java.util.ArrayList；
导入java.awt.*；
导入javax.swing.*；
导入java.awt.event.*；
公共类多线程扩展JApplet{
公共多线程（）{
添加（新的BallControl（））；
}
类BallControl扩展了JPanel{
专用BallPanel BallPanel=新的BallPanel（）；
私有JButton Suspend=新JButton（“Suspend”）；
私有JButton Resume=新JButton（“Resume”）；
私有JButton Add=新JButton（“+1”）；
私有JButton Subtract=新JButton（“-1”）；
private JScrollBar Delay=new JScrollBar（）；
公共控制（）{
//将面板中的按钮分组
JPanel面板=新的JPanel（）；
面板。添加（暂停）；
面板。添加（恢复）；
面板。添加（添加）；
面板。加（减）；
//将球和按钮添加到面板
setboorder（newjavax.swing.border.LineBorder（Color.red））；
延迟。设置方向（JScrollBar。水平）；
setDelay（Delay.getMaximum（））；
setLayout（新的BorderLayout（））；
添加（延迟，边界布局。北）；
添加（ballPanel、BorderLayout.CENTER）；
添加（面板，边界布局。南部）；
//注册侦听器
Suspend.addActionListener（新的Listener（））；
Resume.addActionListener（newlistener（））；
Add.addActionListener（新的Listener（））；
Subtract.addActionListener（newlistener（））；
Delay.addAdjustmentListener（新的AdjustmentListener（）{
公共无效调整值已更改（调整事件e）{
setDelay（Delay.getMaximum（）-e.getValue（））；
}
});
}
类侦听器实现ActionListener{
已执行的公共无效操作（操作事件e）{
如果（如getSource（）==挂起）
ballPanel.suspend（）；
否则如果（例如getSource（）==恢复）
ballPanel.resume（）；
else if（例如getSource（）==Add）
ballPanel.add（）；
else if（例如getSource（）==减法）
ballPanel.subtract（）；
}
}
}
类BallPanel扩展了JPanel{
专用int延迟=30；
private ArrayList list=new ArrayList（）；
//创建一个具有初始延迟的计时器
受保护的计时器=新计时器（延迟，新ActionListener（）{
/**处理操作事件*/
已执行的公共无效操作（操作事件e）{
重新油漆（）；
}
});
公共事务委员会（）{
timer.start（）；
}
公共无效添加（）{
添加（新球（））；
}
公共空减（）{
如果（list.size（）>0）
list.remove（list.size（）-1）；//移除最后一个球
}
@凌驾
受保护组件（图形g）{
超级组件（g）；
g、 drawRect（185279,50,15）；
g、 setColor（Color.RED）；
g、 fillRect（185279,50,15）；
对于（int i=0；igetWidth（））
ball.dx=-ball.dx；
if（ball.y<0 | | ball.y>getHeight（））
ball.dy=-ball.dy；
//调整球位
ball.x+=ball.dx；
//ball.y+=ball.dy；
g、 圆角椭圆（ball.x-ball.radius，ball.y-ball.radius，
球半径*2，球半径*2）；
}
}
公众假期暂停{
timer.stop（）；
}
公众简历（）{
timer.start（）；
}
公共无效设置延迟（整数延迟）{
延迟=延迟；
定时器。设置延迟（延迟）；
}
}
班级舞会{
int x=20；
int y=20；//当前球位置
int dx=2；//球的x坐标增量
int dy=2；//球的y坐标增量
int半径=15；//球半径
颜色=新颜色（（int）（Math.random（）*256），
（int）（Math.random（）*256），（int）（Math.random（）*256））；
}
/**主要方法*/
公共静态void main（字符串[]args）{
JFrame=新JFrame（）；
JApplet applet=新的MultipleBallApp（）；
frame.add（applet）；
frame.setTitle（“MultipleBallApp”）；
frame.setLocationRelativeTo（null）；//将帧居中
frame.setDefaultCloseOperation（JFrame.EXIT_ON_CLOSE）；
框架。设置尺寸（400400）；
frame.setLocationRelativeTo（null）；//将帧居中
frame.setVisible（true）；
}
}
添加一个静态变量，如ballCount，并在每次制作球时向其添加1。在
Ball
类中，将y的定义更改为类似
y=20+球数*（半径*2+距离球）

公共类随机测试扩展了JApplet{
公共随机测试（）{
添加（新的BallControl（））；
}
静态整数球数=0；
类BallControl扩展了JPanel{
专用BallPanel BallPanel=新的BallPanel（）；
私有JButton Suspend=新JButton（“Suspend”）；
私有JButton Resume=新JButton（“Resume”）；
私有JButton Add=新JButton（“+1”）；
私有JButton Subtract=新JButton（“-1”）；
private JScrollBar Delay=new JScrollBar（）；
公共控制（）{
//将面板中的按钮分组
JPanel面板=新的JPanel（）；
面板。添加（暂停）；
面板。添加（恢复）；
面板。添加（添加）；
面板。加（减）；
//将球和按钮添加到面板
setboorder（newjavax.swing.border.LineBorder（Color.red））；
延迟

public class RandomTests extends JApplet {


    public RandomTests() {
        add(new BallControl());
    }

    static int ballCount = 0;

    class BallControl extends JPanel {
        private BallPanel ballPanel = new BallPanel();
        private JButton Suspend = new JButton("Suspend");
        private JButton Resume = new JButton("Resume");
        private JButton Add = new JButton("+1");
        private JButton Subtract = new JButton("-1");
        private JScrollBar Delay = new JScrollBar();

        public BallControl() {
            // Group buttons in a panel
            JPanel panel = new JPanel();
            panel.add(Suspend);
            panel.add(Resume);
            panel.add(Add);
            panel.add(Subtract);

            // Add ball and buttons to the panel
            ballPanel.setBorder(new javax.swing.border.LineBorder(Color.red));
            Delay.setOrientation(JScrollBar.HORIZONTAL);
            ballPanel.setDelay(Delay.getMaximum());
            setLayout(new BorderLayout());
            add(Delay, BorderLayout.NORTH);
            add(ballPanel, BorderLayout.CENTER);
            add(panel, BorderLayout.SOUTH);

            // Register listeners
            Suspend.addActionListener(new Listener());
            Resume.addActionListener(new Listener());
            Add.addActionListener(new Listener());
            Subtract.addActionListener(new Listener());
            Delay.addAdjustmentListener(new AdjustmentListener() {

                public void adjustmentValueChanged(AdjustmentEvent e) {
                    ballPanel.setDelay(Delay.getMaximum() - e.getValue());
                }
            });
        }

        class Listener implements ActionListener {

            public void actionPerformed(ActionEvent e) {
                if (e.getSource() == Suspend) ballPanel.suspend();
                else if (e.getSource() == Resume) ballPanel.resume();
                else if (e.getSource() == Add) ballPanel.add();
                else if (e.getSource() == Subtract) ballPanel.subtract();
            }
        }
    }

    class BallPanel extends JPanel {
        private int delay = 30;
        private ArrayList<Ball> list = new ArrayList<Ball>();

        // Create a timer with the initial delay
        protected Timer timer = new Timer(delay, new ActionListener() {
            /** Handle the action event */
            public void actionPerformed(ActionEvent e) {
                repaint();
            }
        });

        public BallPanel() {
            timer.start();
        }

        public void add() {
            list.add(new Ball());
            ballCount++;
        }

        public void subtract() {
            if (list.size() > 0) list.remove(list.size() - 1); // Remove the last ball
        }

        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
            g.drawRect(185, 279, 50, 15);
            g.setColor(Color.RED);
            g.fillRect(185, 279, 50, 15);

            for (int i = 0; i < list.size(); i++) {
                Ball ball = (Ball) list.get(i); // Get a ball
                g.setColor(ball.color); // Set ball color

                // Check boundaries
                if (ball.x < 0 || ball.x > getWidth()) ball.dx = -ball.dx;

                if (ball.y < 0 || ball.y > getHeight()) ball.dy = -ball.dy;

                // Adjust ball position
                ball.x += ball.dx;
                // ball.y += ball.dy;
                g.fillOval(ball.x - ball.radius, ball.y - ball.radius, ball.radius * 2, ball.radius * 2);
            }
        }

        public void suspend() {
            timer.stop();
        }

        public void resume() {
            timer.start();
        }

        public void setDelay(int delay) {
            this.delay = delay;
            timer.setDelay(delay);
        }
    }

    class Ball {
        int radius = 15; // Ball radius
        int x = radius;
        int y = 20 + (radius * ballCount * 2 + 15); // Current ball position
        int dx = 2; // Increment on ball's x-coordinate
        int dy = 2; // Increment on ball's y-coordinate
        Color color = new Color((int) (Math.random() * 256), (int) (Math.random() * 256), (int) (Math.random() * 256));
    }

    public static void main(String[] args) {
        JFrame frame = new JFrame();
        JApplet applet = new RandomTests();
        frame.add(applet);
        frame.setTitle("MultipleBallApp");
        frame.setLocationRelativeTo(null); // Center the frame
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(400, 400);
        frame.setLocationRelativeTo(null); // Center the frame
        frame.setVisible(true);
    }
}



public interface AnimatedShape {
    public void update(Rectangle bounds);
    public void paint(JComponent parent, Graphics2D g2d);
}



public abstract class AbstractAnimatedShape implements AnimatedShape {

    private Rectangle bounds;
    private int dx, dy;

    public AbstractAnimatedShape() {
    }

    public void setBounds(Rectangle bounds) {
        this.bounds = bounds;
    }

    public Rectangle getBounds() {
        return bounds;
    }

    public int getDx() {
        return dx;
    }

    public int getDy() {
        return dy;
    }

    public void setDx(int dx) {
        this.dx = dx;
    }

    public void setDy(int dy) {
        this.dy = dy;
    }

    @Override
    public void update(Rectangle parentBounds) {
        Rectangle bounds = getBounds();
        int dx = getDx();
        int dy = getDy();
        bounds.x += dx;
        bounds.y += dy;
        if (bounds.x  < parentBounds.x) {
            bounds.x = parentBounds.x;
            setDx(dx *= -1);
        } else if (bounds.x + bounds.width > parentBounds.x + parentBounds.width) {
            bounds.x = parentBounds.x + (parentBounds.width - bounds.width);
            setDx(dx *= -1);
        }
        if (bounds.y < parentBounds.y) {
            bounds.y = parentBounds.y;
            setDy(dy *= -1);
        } else if (bounds.y + bounds.height > parentBounds.y + parentBounds.height) {
            bounds.y = parentBounds.y + (parentBounds.height - bounds.height);
            setDy(dy *= -1);
        }
    }
}



public class AnimatedBall extends AbstractAnimatedShape {

    private Color color;

    public AnimatedBall(int x, int y, int radius, Color color) {
        setBounds(new Rectangle(x, y, radius * 2, radius * 2));
        this.color = color;
        setDx(Math.random() > 0.5 ? 2 : -2);
        setDy(Math.random() > 0.5 ? 2 : -2);
    }

    public Color getColor() {
        return color;
    }

    @Override
    public void paint(JComponent parent, Graphics2D g2d) {
        Rectangle bounds = getBounds();
        g2d.setColor(getColor());
        g2d.fillOval(bounds.x, bounds.y, bounds.width, bounds.height);
    }
}



private ArrayList<AnimatedShape> list = new ArrayList<AnimatedShape>();



protected Timer timer = new Timer(delay, new ActionListener() {
    @Override
    public void actionPerformed(ActionEvent e) {
        for (AnimatedShape ball : list) {
            ball.update(getBounds());
        }
        repaint();
    }
});



@Override
protected void paintComponent(Graphics g) {
    super.paintComponent(g);

    Graphics2D g2d = (Graphics2D) g;
    for (AnimatedShape ball : list) {
        ball.paint(this, g2d);
    }
}



public void add() {
    int radius = 15;
    // Randomised position
    int x = (int)(Math.random() * (getWidth() - (radius * 2))) + radius;
    int y = (int)(Math.random() * (getHeight() - (radius * 2))) + radius;
    Color color = new Color((int) (Math.random() * 256),
                    (int) (Math.random() * 256), (int) (Math.random() * 256));

    AnimatedBall ball = new AnimatedBall(x, y, radius, color);

    list.add(ball);
}



import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.AdjustmentEvent;
import java.awt.event.AdjustmentListener;
import java.util.ArrayList;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollBar;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class MultipleBall {

    public MultipleBall() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                JFrame frame = new JFrame("MultipleBallApp");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.add(new BallControl());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class BallControl extends JPanel {

        private BallPanel ballPanel = new BallPanel();
        private JButton Suspend = new JButton("Suspend");
        private JButton Resume = new JButton("Resume");
        private JButton Add = new JButton("+1");
        private JButton Subtract = new JButton("-1");
        private JScrollBar Delay = new JScrollBar();

        public BallControl() {
            // Group buttons in a panel
            JPanel panel = new JPanel();
            panel.add(Suspend);
            panel.add(Resume);
            panel.add(Add);
            panel.add(Subtract);

            // Add ball and buttons to the panel
            ballPanel.setBorder(new javax.swing.border.LineBorder(Color.red));
            Delay.setOrientation(JScrollBar.HORIZONTAL);
            ballPanel.setDelay(Delay.getMaximum());
            setLayout(new BorderLayout());
            add(Delay, BorderLayout.NORTH);
            add(ballPanel, BorderLayout.CENTER);
            add(panel, BorderLayout.SOUTH);

            // Register listeners
            Suspend.addActionListener(new Listener());
            Resume.addActionListener(new Listener());
            Add.addActionListener(new Listener());
            Subtract.addActionListener(new Listener());
            Delay.addAdjustmentListener(new AdjustmentListener() {

                public void adjustmentValueChanged(AdjustmentEvent e) {
                    ballPanel.setDelay(Delay.getMaximum() - e.getValue());
                }
            });
        }

        class Listener implements ActionListener {

            public void actionPerformed(ActionEvent e) {
                if (e.getSource() == Suspend) {
                    ballPanel.suspend();
                } else if (e.getSource() == Resume) {
                    ballPanel.resume();
                } else if (e.getSource() == Add) {
                    ballPanel.add();
                } else if (e.getSource() == Subtract) {
                    ballPanel.subtract();
                }
            }
        }
    }

    class BallPanel extends JPanel {

        private int delay = 30;
        private ArrayList<AnimatedShape> list = new ArrayList<AnimatedShape>();
        private AnimatedRectange rectangle;

        public BallPanel() {
            this.rectangle = new AnimatedRectange(-25, 200, 50, 25, Color.RED);

            timer.start();
        }

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(400, 400);
        }

        // Create a timer with the initial delay
        protected Timer timer = new Timer(delay, new ActionListener() {
            /**
             * Handle the action event
             */
            @Override
            public void actionPerformed(ActionEvent e) {
                for (AnimatedShape ball : list) {
                    ball.update(getBounds());
                }
                rectangle.update(getBounds());
                repaint();
            }
        });

        public void add() {
            int radius = 15;
            // Randomised position
            int x = (int) (Math.random() * (getWidth() - (radius * 2))) + radius;
            int y = (int) (Math.random() * (getHeight() - (radius * 2))) + radius;
            Color color = new Color((int) (Math.random() * 256),
                            (int) (Math.random() * 256), (int) (Math.random() * 256));

            AnimatedBall ball = new AnimatedBall(x, y, radius, color);

            list.add(ball);
        }

        public void subtract() {
            if (list.size() > 0) {
                list.remove(list.size() - 1); // Remove the last ball
            }
        }

        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);

            Graphics2D g2d = (Graphics2D) g;
            for (AnimatedShape ball : list) {
                ball.paint(this, g2d);
            }
            rectangle.paint(this, g2d);
        }

        public void suspend() {
            timer.stop();
        }

        public void resume() {
            timer.start();
        }

        public void setDelay(int delay) {
            this.delay = delay;
            timer.setDelay(delay);
        }
    }

    public interface AnimatedShape {

        public void update(Rectangle bounds);

        public void paint(JComponent parent, Graphics2D g2d);
    }

    public abstract class AbstractAnimatedShape implements AnimatedShape {

        private Rectangle bounds;
        private int dx, dy;

        public AbstractAnimatedShape() {
        }

        public void setBounds(Rectangle bounds) {
            this.bounds = bounds;
        }

        public Rectangle getBounds() {
            return bounds;
        }

        public int getDx() {
            return dx;
        }

        public int getDy() {
            return dy;
        }

        public void setDx(int dx) {
            this.dx = dx;
        }

        public void setDy(int dy) {
            this.dy = dy;
        }

        @Override
        public void update(Rectangle parentBounds) {
            Rectangle bounds = getBounds();
            int dx = getDx();
            int dy = getDy();
            bounds.x += dx;
            bounds.y += dy;
            if (bounds.x  < parentBounds.x) {
                bounds.x = parentBounds.x;
                setDx(dx *= -1);
            } else if (bounds.x + bounds.width > parentBounds.x + parentBounds.width) {
                bounds.x = parentBounds.x + (parentBounds.width - bounds.width);
                setDx(dx *= -1);
            }
            if (bounds.y < parentBounds.y) {
                bounds.y = parentBounds.y;
                setDy(dy *= -1);
            } else if (bounds.y + bounds.height > parentBounds.y + parentBounds.height) {
                bounds.y = parentBounds.y + (parentBounds.height - bounds.height);
                setDy(dy *= -1);
            }
        }
    }

    public class AnimatedBall extends AbstractAnimatedShape {

        private Color color;

        public AnimatedBall(int x, int y, int radius, Color color) {
            setBounds(new Rectangle(x, y, radius * 2, radius * 2));
            this.color = color;
            setDx(Math.random() > 0.5 ? 2 : -2);
            setDy(Math.random() > 0.5 ? 2 : -2);
        }

        public Color getColor() {
            return color;
        }

        @Override
        public void paint(JComponent parent, Graphics2D g2d) {
            Rectangle bounds = getBounds();
            g2d.setColor(getColor());
            g2d.fillOval(bounds.x, bounds.y, bounds.width, bounds.height);
        }
    }

    public class AnimatedRectange extends AbstractAnimatedShape {

        private Color color;

        public AnimatedRectange(int x, int y, int width, int height, Color color) {
            setBounds(new Rectangle(x, y, width, height));
            this.color = color;
            setDx(2);
        }

        // Don't want to adjust the vertical speed
        @Override
        public void setDy(int dy) {
        }

        @Override
        public void paint(JComponent parent, Graphics2D g2d) {
            Rectangle bounds = getBounds();
            g2d.setColor(color);
            g2d.fill(bounds);
        }

    }

    /**
     * Main method
     */
    public static void main(String[] args) {
        new MultipleBall();
    }
}