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copied!<p>I propose a simple, but well-working solution, found out by myself ;)</p> <p>What do I do?</p> <ul> <li>When mouse is pressed, I record the <strong>cursor's</strong> position <strong>on screen</strong>, and the <strong>component's</strong> position.</li> <li>When mouse is dragged, I calculate the <strong>difference</strong> between new and old <strong>cursor's</strong> position <strong>on screen</strong>, and move the component <strong>by this difference</strong>.</li> </ul> <p><em>Tested with latest JDK 6 unter Linux (OpenSuse, KDE3),<br> but hey, it's Java Swing, should work equally everywhere.</em></p> <p><strong>Here goes the code:</strong></p> <pre><code>import java.awt.*; import java.awt.event.*; import javax.swing.*; import javax.swing.border.*; public class MyDraggableComponent extends JComponent { private volatile int screenX = 0; private volatile int screenY = 0; private volatile int myX = 0; private volatile int myY = 0; public MyDraggableComponent() { setBorder(new LineBorder(Color.BLUE, 3)); setBackground(Color.WHITE); setBounds(0, 0, 100, 100); setOpaque(false); addMouseListener(new MouseListener() { @Override public void mouseClicked(MouseEvent e) { } @Override public void mousePressed(MouseEvent e) { screenX = e.getXOnScreen(); screenY = e.getYOnScreen(); myX = getX(); myY = getY(); } @Override public void mouseReleased(MouseEvent e) { } @Override public void mouseEntered(MouseEvent e) { } @Override public void mouseExited(MouseEvent e) { } }); addMouseMotionListener(new MouseMotionListener() { @Override public void mouseDragged(MouseEvent e) { int deltaX = e.getXOnScreen() - screenX; int deltaY = e.getYOnScreen() - screenY; setLocation(myX + deltaX, myY + deltaY); } @Override public void mouseMoved(MouseEvent e) { } }); } } public class Main { public static void main(String[] args) { JFrame f = new JFrame("Swing Hello World"); // by doing this, we prevent Swing from resizing // our nice component f.setLayout(null); MyDraggableComponent mc = new MyDraggableComponent(); f.add(mc); f.setSize(500, 500); f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); f.setVisible(true); } } </code></pre>

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