How to include Time delay in GUI enviroment

Question

hi all,
i want to include time delay while drawing the shapes in the Canvas. I tried with Thread.sleep() and also delaying methods by making them to loop for large number of times.... but it affects the repainting of my Frame window like just previously executed snippet of the code gets repeated again and the delay between the shapes drawn cannot be visually seen..
Can anyone help me????

Answer 1

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class DrawingExample extends JPanel implements ActionListener {
    private Timer timer = new Timer(200, this);
    private Rectangle[] rects = new Rectangle[10];
    private int currentUB;
    private boolean desc;
    public DrawingExample() {
        for(int i=0; i<rects.length; ++i)
            rects[i] = new Rectangle(i*15, i*15, 40, 40);
        timer.start();
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        Graphics2D g2 = (Graphics2D) g;
        for(int i=0; i<currentUB; ++i)
            g2.draw(rects);
public static void main(String[] args) {
EventQueue.invokeLater(buildApp);
public void actionPerformed(ActionEvent evt) {
currentUB += desc ? -1 : +1;
if (currentUB == -1) {
desc = false;
currentUB = 1;
} else if (currentUB == rects.length+1) {
desc = true;
currentUB = rects.length-1;
repaint();
static Runnable buildApp = new Runnable() {
public void run() {
JComponent comp = new DrawingExample();
comp.setPreferredSize(new Dimension(300,300));
JFrame f = new JFrame();
f.getContentPane().add(comp);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);