How to paint on a Netbean 6.5 generated applet?

Hello everyone:

I wish to create an applet using Netbeans 6.5 and paint on it with instructions as, for example,

gr.setColor(Color.YELLOW);
gr.fillRect(10, 10, 100, 100);
etc.

I created an applet according to Netbeans help instructions, that is:

File/New project/Java/Java class library…
Later:
I right clicked over the project icon /New/Other/Swing GUI forms/JApplet form.

I have added controls etc.. but I’m not able to paint anything on the applet.
I tried many ways…,

I have created my own panel class extended from JPanel and overrode the paint() method…,
I have obtained the graphics context by getGraphics()…,
I have added Internal frame to my main class (extended from JApplet) etc.

but always unsuccessfully.

Source code compiles fine, no errors reported, but I only see the controls added, never what I tried to paint.

Could you please let me know what should I do to paint something on the applet?

Sorry, I have been studying Java only since two weeks ago.

Thanks a lot in advance
Pucho

Note: I can paint on a simple applet (not using Swing) but losing all of the Swing advantages.

I read that I should use a JPanel, override its paintComponent() method, having as the first line a call to super.paintComponent(g); and then add the JPanel to the JApplet's contentPane.

However:
1) If I visually drag a JPanel to the JApplet’s content pane I don’t know how to override the paintComponent() method.

2) On the other hand, if I create a new class “MyPanel” extended from JPanel and add it (not visually but using the code) to the JApplet’s content pane, I can override the paintComponent() method but I cannot see MyPanel in the Design view so I cannot drag and drop controls . In addition I cannot see neither what I tried to paint , see applet’s code below.

//------------------------------------------------------
package AP001Package;
import java.awt.*;
import javax.swing.BorderFactory;

public class AP001class extends javax.swing.JApplet {
@Override
public void init() {
try {
java.awt.EventQueue.invokeAndWait(new Runnable() {
public void run() {
add(new MyPanel());
initComponents();

}
});
} catch (Exception ex) {
ex.printStackTrace();
}
}

@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">

}

class MyPanel extends javax.swing.JPanel
{
public MyPanel() {
setBorder(BorderFactory.createLineBorder(Color.bla ck));
}

@Override
public Dimension getPreferredSize() {
return new Dimension(250,200);
}

@Override
public void paintComponent(Graphics g){
super.paintComponent(g);
g.setColor(Color.YELLOW);
g.fillRect(10, 10, 100, 100);
}
}