In my JApplet, I am able to change the background color of the panel but not the currentSurface which is an instance of PaintSurface extends JComponent. Could someone please help me out? Many thanks

import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.awt.geom.*;
public class Tanks extends JApplet
{
 public static final int WIDTH  = 400;
 public static final int HEIGHT = 400;
 private JButton button1;
 private PaintSurface currentSurface = new PaintSurface();
 public Tanks()
 { 
  this.add(currentSurface,BorderLayout.CENTER);
  ButtonListener b1 = new ButtonListener();
  JPanel panel = new JPanel();
  [B]panel.setBackground(Color.white);[/B]
[B] currentSurface.setBackground(Color.white);[/B]
  button1 = new JButton("Start");
  button1.addActionListener(b1);
  panel.add(button1);
  this.add(panel,BorderLayout.NORTH);
 }
 
 public void init()
 {
  this.setSize(WIDTH, HEIGHT);
  this.setVisible(true);
 
 }
 
 private class ButtonListener implements ActionListener
 {
 
  public void actionPerformed(ActionEvent e)
  {
   if(e.getActionCommand() == "Start")
   {
    currentSurface.figure="Start";
    repaint();
   }
  }
 
 }
}
 
class AnimationThread extends Thread
{
 JApplet c;
 public AnimationThread(JApplet c)
 {
  this.c = c;
 }
 public void run()
 {
 }
}
 
class PaintSurface extends JComponent
{
 String figure;
 
 public PaintSurface()
 {
 }
 public void paint(Graphics g)
 {
  Graphics2D g2 = (Graphics2D)g;
  g2.setRenderingHint(
   RenderingHints.KEY_ANTIALIASING,
   RenderingHints.VALUE_ANTIALIAS_ON);
 
  if(figure=="Start")
  {
   Shape s = new Ellipse2D.Float(20,50,250,150);
   g2.setPaint(Color.BLACK);
   g2.draw(s);
  }
 
 }
}

You should be overriding paintComponent, and not paint. You also need to call setOpaque on the component.

You should be overriding paintComponent, and not paint. You also need to call setOpaque on the component.

Thanks

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