Jumping JDialog

Question

Ive read some posts about this but neither of them really answer the question about why this is happening and how do i solve it, so i will throw it out to all of you geniuses for help.
The problem is that when I create the undecorated jdialog and try to drag it using my own mouse handler. When you drag it for long periods of time it starts to flicker and jump all over the screen. Here's the code, try it out and let me know if you figure anything out.
Compile and run, and then click the large button. A small bordered panel will appear somewhere near the middle of the screen. Grab an area with the mouse not far from the northern part of the new little panel. Start to drag it for a bit, all over the screen. After a short while, the box will begin to fly all over the place uncontrollably. Therein lies the problem.
Thanks in advance
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;
import java.awt.image.BufferedImage;
import javatest.components.BlankFrame.BlankRootPane;
import javax.swing.AbstractAction;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.border.LineBorder;
* @author atom
public class JumpingJDialog extends JDialog
    private static int xLocation = 400;
    private static int yLocation = 400;
     * Creates a new instance of JumpingJDialog
    public JumpingJDialog(JFrame parent)
        super(parent, "", false);
        setUndecorated(true);
        setFocusable(false);
        setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
        setAlwaysOnTop(true);
        setResizable(false);
        setLocation(xLocation, yLocation);
        setSize(300, 75);
        panel.setLayout(new BorderLayout());
        panel.setBorder(new LineBorder(Color.BLACK, 1));
        panel.add(new TitleBar(), BorderLayout.NORTH);
        add(panel);
    JPanel panel = new JPanel();
    private class TitleBar extends JPanel
        public TitleBar()
            setPreferredSize(new Dimension(getWidth(), 7));
            setOpaque(false);
            addMouseListener(ml);
            addMouseMotionListener(ml);
        TitleBarMouseListener ml = new TitleBarMouseListener();
        private class TitleBarMouseListener extends MouseAdapter implements MouseMotionListener
            double oldX, oldY;
             * Invoked when a mouse button is pressed on a component and then
             * dragged.  <code>MOUSE_DRAGGED</code> events will continue to be
             * delivered to the component where the drag originated until the
             * mouse button is released (regardless of whether the mouse position
             * is within the bounds of the component).
             * <p>
             * Due to platform-dependent Drag&Drop implementations,
             * <code>MOUSE_DRAGGED</code> events may not be delivered during a native
             * Drag&Drop operation.
            public void mouseDragged(MouseEvent e)
                Point p = JumpingJDialog.this.getLocation();
                Point mp = e.getPoint();
                SwingUtilities.convertPointToScreen(mp, TitleBar.this);
                if (oldX < 0 || oldY < 0)
                    oldX = mp.x;
                    oldY = mp.y;
                else
                    if (mp.x >= 0 && mp.y >= 0)
                        Toolkit.getDefaultToolkit().sync();
                        double deltax = mp.x - oldX;
                        double deltay = mp.y - oldY;
                        oldX = mp.x + deltax;
                        oldY = mp.y + deltay;
                        Rectangle bounds = JumpingJDialog.this.getBounds();
                        if (bounds.contains(mp))
                            JumpingJDialog.this.setLocation((int)(mp.x-pressedX), (int)(mp.y-pressedY));
                        else
                            JumpingJDialog.this.setLocation((int)mp.x-pressedX, (int)mp.y-pressedY);
            public void mouseMoved(MouseEvent e)
            int pressedX, pressedY;
            public void mousePressed(MouseEvent e)
                pressedX = e.getX();
                pressedY = e.getY();
    public static void main(String[] args)
        SwingUtilities.invokeLater(new Runnable()
            public void run()
                final JFrame frame = new JFrame();
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setSize(640, 480);
                frame.setVisible(true);
                frame.add(new JButton(new AbstractAction("New Dialog")
                    public void actionPerformed(ActionEvent e)
                        JumpingJDialog fd = new JumpingJDialog(frame);
                        fd.setVisible(true);
}

Answer 1

Here is the code for anyone who is interested
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;
import java.awt.image.BufferedImage;
import javax.swing.AbstractAction;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JWindow;
import javax.swing.SwingUtilities;
import javax.swing.border.LineBorder;
* @author atom
public class JumpingJDialog extends JWindow
    private static int xLocation = 400;
    private static int yLocation = 400;
     * Creates a new instance of JumpingJDialog
    public JumpingJDialog(JFrame parent)
        super(parent);
        setFocusable(false);
        setAlwaysOnTop(true);
        setLocation(xLocation, yLocation);
        setSize(300, 75);
        panel.setLayout(new BorderLayout());
        panel.setBorder(new LineBorder(Color.BLACK, 1));
        panel.add(new TitleBar(), BorderLayout.NORTH);
        add(panel);
    JPanel panel = new JPanel();
    private class TitleBar extends JPanel
        public TitleBar()
            setPreferredSize(new Dimension(getWidth(), 7));
            setOpaque(false);
            addMouseListener(ml);
            addMouseMotionListener(ml);
        TitleBarMouseListener ml = new TitleBarMouseListener();
        Point location;
        MouseEvent pressed;
        private class TitleBarMouseListener extends MouseAdapter implements MouseMotionListener
             * Invoked when a mouse button is pressed on a component and then
             * dragged.  <code>MOUSE_DRAGGED</code> events will continue to be
             * delivered to the component where the drag originated until the
             * mouse button is released (regardless of whether the mouse position
             * is within the bounds of the component).
             * <p>
             * Due to platform-dependent Drag&Drop implementations,
             * <code>MOUSE_DRAGGED</code> events may not be delivered during a native
             * Drag&Drop operation.
            public void mousePressed(MouseEvent me)
                pressed = me;
            public void mouseDragged(MouseEvent me)
                location = JumpingJDialog.this.getLocation(location);
                int x = location.x - pressed.getX() + me.getX();
                int y = location.y - pressed.getY() + me.getY();
                JumpingJDialog.this.setLocation(x, y);
                Toolkit.getDefaultToolkit().sync();
            public void mouseMoved(MouseEvent e)
        public void mouseMoved(MouseEvent e)
        int pressedX, pressedY;
        public void mousePressed(MouseEvent e)
            pressedX = e.getX();
            pressedY = e.getY();
    public static void main(String[] args)
        SwingUtilities.invokeLater(new Runnable()
            public void run()
                final JFrame frame = new JFrame();
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setSize(640, 480);
                frame.setVisible(true);
                frame.add(new JButton(new AbstractAction("New Dialog")
                    public void actionPerformed(ActionEvent e)
                        JumpingJDialog fd = new JumpingJDialog(frame);
                        fd.setVisible(true);
}