_hierarchyTreeData(array_values($this->dataProvider->getModels()), $this->rootParentId);
        return $this->renderTreelist($models);
    }
    protected function renderTreelist($models) {
        foreach ($models as $index => $model) {
            $row = $this->renderTreelistItem($model['item']);
            $children = empty($model['children']) ? '' : $this->renderTreelist($model['children']);
            $output[] = '
'. $row . $children .'';
        }
        if (!empty($output))
            return ''. implode("\n", $output) .'
';
    }
    protected function renderTreelistItem($model)
    {
        $options = [];
        $id = ArrayHelper::getValue($model, $this->keyNameId);
        Html::addCssClass($options, "treelistitem-$id");
        $parent_id = ArrayHelper::getValue($model, $this->keyNameParentId);
        if ($parent_id) {
            Html::addCssClass($options, "treelistitem-parent-$parent_id");
        }
//        if (is_string($this->value)) {
//            return ArrayHelper::getValue($model, $this->value);
//        } else {
//            return call_user_func($this->value, $model, $key, $index, $this);
//        }
        return Html::tag('span', ArrayHelper::getValue($model, $this->displayField), $options);
    }
}