Object flickers when dragged

Question

i'm trying to write an app in which i can drag swing components around using mouse. i modified the LayeredPaneDemo in teh swing tutorial as a test.
the component i'm trying to drag is aJPanel, since it's a container, it can contain other components, so when i drag it, all components within teh panel should move all together - i registered teh mous listener on teh panel.
for this test. the jpanel has a button with icon, and a label.
but whe i drag the panel, it flickers badly, and i sees 2 panels.
however, if i register teh listener on the button, the flickering will dispear, but only teh button will be moved around, teh label stays at the same spot. thx in advance.
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class DragTest {
    public static void main(String[] args) {
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setSize(new Dimension(400, 400));
        Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
        int x = screenSize.width/2 - frame.getSize().width/2;
        int y = screenSize.height/2 - frame.getSize().height/2;
        frame.setLocation(x, y);
        Container c = frame.getContentPane();
        c.add(new Draggable(), null);
        frame.setVisible(true);
class Draggable extends JPanel{
    private final JButton dukeButton;
    private final JPanel p;
    private final ImageIcon icon;
    public Draggable(){
        //Create and load the duke icon.
        icon = new ImageIcon("images/dukeWaveRed.gif");
        dukeButton = new JButton(icon);
        dukeButton.setDoubleBuffered(true);
        p = this;
        dukeButton.addMouseMotionListener(new MouseMotionAdapter() {
            public void mouseDragged(MouseEvent e) {
                p.setLocation(e.getX(), e.getY());
                //dukeButton.setLocation(e.getX(), e.getY());
        this.add(dukeButton, null);
        this.add(new JLabel("hello"));

Answer 1

i got it! the problem was that i wasn't translating the event corrodinates correctly. the e.getX() and getY() merely returns the x,y location within teh panel, after i do:
p = this;
this.addMouseMotionListener(new MouseMotionAdapter() {
            public void mouseDragged(MouseEvent e) {
                p.setLocation(p.getX()+e.getX(), p.getY()+e.getY());
        });it moved smoothly =o)