public function collectItems(CollectItemsEvent $event)
 {
     $item = $event->getParentItem();
     if ($item->getType() == 'page') {
         if (empty($this->columns)) {
             return;
         }
         $columnWildcards = array_fill(0, count($this->columns), '?');
         $columnWildcards = implode(',', $columnWildcards);
         $t = \ArticleModel::getTable();
         $arrColumns = array("{$t}.pid=?", "{$t}.inColumn IN ({$columnWildcards})");
         if (!BE_USER_LOGGED_IN) {
             $time = time();
             $arrColumns[] = "({$t}.start='' OR {$t}.start<{$time}) AND ({$t}.stop='' OR {$t}.stop>{$time}) AND {$t}.published=1";
         }
         $articles = \ArticleModel::findBy($arrColumns, array_merge(array($item->getName()), $this->columns), array('order' => 'sorting'));
         if ($articles) {
             $factory = $event->getFactory();
             foreach ($articles as $article) {
                 $factory->createItem('article', $article->id, $item);
             }
         }
     }
 }