Moving a component...

[crptcblade]

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...

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.

[Dillinger4]

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. Ill have to look at my code again tommorow.

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());
   }
}

[crptcblade]

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.