* involves the canvas.
*/
protected void initializeInteraction() {
GraphPane pane = getGraphPane();
_menuFactory = new SchematicContextMenuFactory(this);
_menuCreator = new MenuCreator(_menuFactory);
_menuCreator.setMouseFilter(new PopupMouseFilter());
// Note that the menuCreator cannot be an interactor, because
// it accepts all events.
// NOTE: The above is a very strange comment, since