protected function _getColNames($sId = null)
    {
        if ($sId === null) {
            $sId = \OxidEsales\Eshop\Core\Registry::getConfig()->getRequestParameter('cmpid');
        }

        if ($sId && isset($this->_aColumns[$sId])) {
            return $this->_aColumns[$sId];
        }

        return $this->_aColumns;
    }