code: @Override
      public void dragEntered(final DragEvent dragEvent) {
          // System.out.println("drag ENTERED");
          if (dragEvent.getGestureSource() != controller().view().getBox()
                  && dragEvent.getDragboard().hasContent(CustomDataFormat.DOCKABLE)) {
  
              // getController().getView().drawMarker(dragEvent.getX(), dragEvent.getY());
  
              // getController().getView().getBox().setBorder(new Border(new BorderStroke(Color.AQUAMARINE, BorderStrokeStyle.SOLID, new CornerRadii(1.0), BorderStroke.THICK)));
          }
  
          dragEvent.consume();
      }
docs: {@inheritDoc}