Moving a component...

Say I've got a JFrame with a null Layout. I'm trying to move a component in the JFrame when the mouseDragged event for the component is fired (Similar to how a Windows Listview works when you drag the column header). I just can't seem to get the arithmetic to position it.

So far, I've got...

Code:

---

Point mPMouseDown = new Point();
public void mousePressed(MouseEvent me)
{
        isArmed = true;
        mPMouseDown.setLocation((int)me.getX(),(int)me.getY());
        this.repaint();
}

public void mouseDragged(MouseEvent me)
{
        int t = (int)mPMouseDown.getY();
        int l = (int)mPMouseDown.getX();

        this.setLocation((int)this.getLocation().getX()+(l/2),(int)this.getLocation().getY());

}

---

The code in mouseDragged is completely awful, but I forget the code I had that worked better. What I'm basically looking for is, if the mouse is pressed say 4 pixels in to the component, when I drag, I want the left of the component to stay 4 pixels left of the mouse until I release it.

:)

Here's my stab at this problem. But the only problem is that when the mouse is dragged within the JButton the JButton goes nuts and runs away. :eek: :p Ill have to look at my code again tommorow.

Code:

---

public class DragDrop{
  public static void main(String[] args){
 
  boolean pressed = false;
  JButton dragme = new JButton("Drag Me!");
  dragme.addMouseMotionListener(new Dragged(dragme));
  dragme.setSize(50,25);
  JFrame dragdrop = new JFrame("DragDrop");

  Container content = dragdrop.getContentPane();
  content.setLayout(null);
  content.add(dragme); // start xy at 0
 
  dragdrop.addWindowListener(new WindowAdapter(){
      public void windowClosing(WindowEvent e){
      System.exit(0);
    }
  });

  dragdrop.setSize(400,300);
  dragdrop.setVisible(true);
    }
  }

class Dragged extends MouseMotionAdapter{
JButton dragme;
  public Dragged(JButton dragme){
      this.dragme = dragme;
     
  }
  public void mouseDragged(MouseEvent e){
    dragme.setLocation(e.getY(),e.getX());
  }
}

---

Code:

---

public void mouseDragged(MouseEvent me)
{
          me = SwingUtilities.convertMouseEvent(this,me,me.getComponent().getParent());
        this.setLocation((int)(me.getX()-(this.getWidth()/2)),(int)this.getLocation().getY());
}

---

I came up with this a few minutes ago, it seems to work pretty well.

:)