code: public function getRenderGroupAttribute()
      {
          if (!empty($this->data['rendergroupattr'])) {
              $metaModel = $this->getMetaModel();
              if ($metaModel) {
                  $attribute = $metaModel->getAttributeById($this->data['rendergroupattr']);
                  if ($attribute) {
                      return $attribute->getColName();
                  }
              }
          }
  
          return '';
      }
docs: {@inheritDoc}