* @param elem the element to align to
* @param pos the {@link El#alignTo} anchor position to use in aligning to the
* element (defaults to defaultAlign)
*/
public void show(Element elem, String pos) {
MenuEvent me = new MenuEvent(this);
if (fireEvent(Events.BeforeShow, me)) {
RootPanel.get().add(this);
showing = true;
el().makePositionable(true);