UIGroupNavigationManagement uicomp = event.getSource();
SiteKey siteKey = navigation.getKey();
// open a add navigation popup
UIPopupWindow popUp = uicomp.getChild(UIPopupWindow.class);
UIPageNavigationForm pageNavigation = popUp.createUIComponent(UIPageNavigationForm.class, null, null, popUp);
pageNavigation.setOwnerId(siteKey.getName());
pageNavigation.setOwnerType(siteKey.getTypeName());
pageNavigation.setPriority(String.valueOf(navigation.getPriority()));
pageNavigation.addFormInput();
pageNavigation.setUserNav(navigation);