Applet to draw rectanlge changing color randomly

Question

hello ,
i am new to java and learning applets . i want to draw a rectangle which changes its color randomly .
my issue is i dont know how to set variable in
function setColor()
please help me to implement this applet .
thanks in advance !
gagan

Answer 1

I've done something like so:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import javax.swing.JPanel;
import javax.swing.Timer;
public class AppletPanel extends JPanel
  private static final int DELAY = 160;
  private static final int RANDOM_COLOR_COUNT = 100;
  // use some of the standard colors in an array
  private Color[] colors =
    Color.white, Color.black, Color.red, Color.orange,
    Color.green, Color.blue, Color.cyan, Color.magenta, Color.YELLOW 
  private Color myColor = Color.white;
  List<Color> colorList = new ArrayList<Color>();
  private Random random = new Random();
  private int delay = DELAY;
  Timer timer = new Timer(delay, new ActionListener()
    public void actionPerformed(ActionEvent e)
      myColor = colorList.get(random.nextInt(colorList.size()));
      setBackground(myColor);
  public AppletPanel()
    setPreferredSize(new Dimension(250, 250));
    for (int i = 0; i < colors.length; i++)
      // here we use a Color List to hold the standard colors
      colorList.add(colors);
for (int i = 0; i < RANDOM_COLOR_COUNT; i++)
Color c = new Color(
random.nextInt(256),
random.nextInt(256),
random.nextInt(256));
// and now stuff the list with random colors too!
colorList.add(c);
timer.start();
and for the applet part:
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import javax.swing.BorderFactory;
import javax.swing.JApplet;
public class AppletPanelTest extends JApplet
  public void init()
    try
      javax.swing.SwingUtilities.invokeAndWait(new Runnable()
        public void run()
          createGUI();
    catch (Exception e)
      System.err.println("createGUI didn't successfully complete");
  private void createGUI()
    setSize(new Dimension(400, 300));
    AppletPanel panel = new AppletPanel();
    panel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
    Container contentPane = getContentPane();
    contentPane.setLayout(new FlowLayout());
    contentPane.add(panel);