Multiple bouncing balls thread issue

Question

I created a program that makes multiple bouncing balls with random color, speed and radius. When user clicks on the screen a new random ball should appear and move around sc

Answer 1

You Can try this alternate Java Programm for bouncing 10 multi-colored balls on a single "START" button.....

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import javax.swing.*;
import javaimage.io.*;

class Thr extends Thread
{
    boolean up=false;
    Ballbounce parent;
    int top,left;
    Color c;

    Thr(int t,int l,Color cr,ex5 p)
    {
        top=l;
        if(top > 170)
        top=170-t/8;
        left=t;
        c=cr;
        parent=p;
    }

    public void run()
    {
    try
    {
        while(true)
        {
            Thread.sleep(37);
            if(top >= 188)
            up=true;
            if(top <= 0)
            up=false;
            if(!up)
            top=top+2;
            else
            top=top-2;
            parent.p.repaint();
        }
    }catch(Exception e){}
}
}

    class Ballbounce extends JFrame implements ActionListener
{
int top=0,left=0,n=0,radius=50;
Color C[]={Color.black,Color.cyan,Color.orange,Color.red,Color.yellow,Color.pink,Color.gray,Color.blue,Color.green,Color.magenta};
Thr t[]=new Thr[10];
GPanel p;
JButton b;
Panel  p1;

Ballbounce()
{
setSize(700,300);
setVisible(true);
setLayout( new BorderLayout());
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
add(p=new GPanel(this),BorderLayout.CENTER);

b= new JButton("Start");
b.addActionListener(this);


add(p1=new Panel(),BorderLayout.SOUTH);
p1.setBackground(Color.lightGray);
p1.add(b);
}

public static void main(String args[])
{
new Ballbounce();
}

public void actionPerformed(ActionEvent e)
{
t[n]=new Thr(left+(radius+13)*n+29,top+n*25,C[n],this);
t[n].start();
n++;
p.repaint();
if(n >9)
b.setEnabled(false);
}
}

class GPanel extends JPanel
{
Ballbounce parent;

GPanel(Ballbounce p)
{
 parent=p;
}

public void paintComponent(Graphics g)
{
super.paintComponent(g);
setBackground(Color.white);

for(int i=0;i< parent.n;i++)
{
g.setColor(parent.t[i].c);
g.fillOval(parent.t[i].left,parent.t[i].top,parent.radius,parent.radius);
}
}
}

I hope you will like it.... If u are unable to understand the code... You can question it anytime...... :) Enjoy the code... :)