Random Panel Color in Java

Summary

Colors in computers are generally made up using RGB mode i.e. Red, Green, Blue.

So in java if we generate random color values for RGB from 0 to 255 each we can make a whole new color out of it by passing this RGB to the color object.

To show the demo Swings have been used where the components are JFrame, JPanel & JButton placed using BorderLayout onto center & south.

The ActionListener for the button does the job of changing the background color of the panel.

Screenshot

Code

package com.rohansakhale.randomcolorpaneldemo;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;

/**
 *
 * @author Rohan Sakhale
 */
public class RandomColorPanelDemo {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        JFrame jf = new JFrame("Random Color Demo by rohansakhale");
        JButton jb = new JButton("Change Color");
        final JPanel jp = new JPanel();
 
        jf.add(jp);
        jf.add(BorderLayout.SOUTH, jb);
 
        jb.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
                int red, green, blue;
                red = (int) (Math.random() * 255);
                green = (int) (Math.random() * 255);
                blue = (int) (Math.random() * 255);
                Color c = new Color(red, green, blue);
                jp.setBackground(c);
            }
        });
 
        jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        jf.setSize(400, 300);
        jf.setVisible(true);
    }
}