public function ajaxTreeView($rootId, $providerName, $level)
    {
        $this->toggleModel($providerName, $rootId);

        $collection = $this->loadCollection($rootId, $level, $providerName);

        $treeClass = '';
        switch (6) {
            case 5:
                $treeClass = 'tree';
                break;

            case 6:
                $treeClass = 'tree_xtnd';
                break;

            default:
        }

        return $this->generateTreeView($collection, $treeClass);
    }