_menuCreator = new MenuCreator(null);
_menuCreator.setMouseFilter(new PopupMouseFilter());
// FIXME: Why doesn't getNodeInteractor() return a NodeInteractor?
NodeInteractor interactor = (NodeInteractor) getNodeInteractor();
interactor.addInteractor(_menuCreator);
// The contents of the menu is determined by the associated
// menu factory, which is a protected member of this class.
// Derived classes can add menu items to it.
_menuFactory = new PtolemyMenuFactory(controller);