/**
  * Sorts item's children right before rendering
  * @return array
  */
 public static function sortItems(NavigationNode $component)
 {
     $items = (array) $component->getComponents();
     switch ($component->getSortBy()) {
         case self::SORT_NONE:
             break;
         case self::SORT_PRIORITY:
             usort($items, array(get_class(), 'comparePriority'));
             break;
         case self::SORT_PRIORITY_INTEGER:
             usort($items, array(get_class(), 'comparePriorityInteger'));
             break;
         case self::SORT_PRIORITY_STRING:
             usort($items, array(get_class(), 'comparePriorityString'));
             break;
         case self::SORT_LABEL:
             usort($items, array(get_class(), 'compareLabel'));
             break;
     }
     return $items;
 }