public void showPopupMenu(MouseEvent mouseEvent) {

    // Create the popup menu.
    JPopupMenu popupMenu =
        DockingManager.getComponentFactory().createPopupMenu(draggedDockable, null);

    // Show the popup menu.
    if (popupMenu != null) {
      popupMenu.show(mouseEvent.getComponent(), mouseEvent.getX(), mouseEvent.getY());
    }
  }