public void mouseDragged(MouseEvent e) {
	      Point2D.Double p = new Point2D.Double(0,0); // Change mouse coordenates from
	      MyWorldView.SPACE_INVERSE_TRANSFORM.transform(e.getPoint(),p);// pixels to meters.
	   if (currentElement instanceof Ball) {
		      System.out.println("Dragging Ball");
		      ((Ball)currentElement).setPosition(p.getX());
		   }    
		   else if (currentElement instanceof FixedHook){
			  System.out.println("Dragging FixedHook");
		      ((FixedHook)currentElement).setPosition(p.getX());
		   }
		   else if (currentElement instanceof Block){
			  System.out.println("Dragging Block");
		      ((Block)currentElement).setPosition(p.getX());
		   }
		   else if (currentElement instanceof Spring){	   
			  ((Spring)currentElement).detachAend();  
			  ((Spring)currentElement).detachBend();

		      ((Spring)currentElement).setPosition(p.getX());
		      System.out.println("Dragging Spring");
		   }

	      world.repaintView();
   }