Java jLabel从Netbeans“事件”上下文菜单中拖放

Question

I'm trying to drag a jLabel around the screen following the mouse pointer. As I am no expert on GUI programming I'm trying to do it using Netbeans' GUI design facilities.

I click on "events-mousemotion-mousedragged" and then insert the following code:

private void jLabel2MouseDragged(java.awt.event.MouseEvent evt) {                                     
  int x=evt.getX();
  int y=evt.getY();

  jLabel2.setLocation(x, y);
  jLabel2.repaint();  }  

I don't expect this simple piece of code to work marvels, the issue however is that it behaves in an erratic manner, the jLabel pops up and flickers almost everywhere within its container.

If it's of any help, layout is set to absolute.

Thanks.

Answer 1

As MadProgrammer pointed out, that was the issue. This is my mouse drag method:

private void jLabel2MouseDragged(java.awt.event.MouseEvent evt)  {                                     

  Point p = SwingUtilities.convertPoint(evt.getComponent(), evt.getPoint(), getContentPane());
  int x=p.x;
  int y=p.y;

  jLabel2.setLocation(x-120, y-120);
  jLabel2.repaint();

}   

The jLabel now moves smoothly.

My label is roughly 240x240 pixels, so I corrected the coordinates to have the center of the label placed where the mouse pointer is.

Thanks!