protected function queryVars()
    {
        $resultColumns = $this->dataRecord->getDataSingleton()->getSearchFields();
        $columns = [];
        foreach ($resultColumns as $field) {
            $columns[$field->getName()] = '';
        }

        $arr = array_merge(
            $columns,
            [
                'action_doRegistryFilter' => 'Filter',
                'Sort' => '',
                'Dir' => ''
            ]
        );

        foreach ($arr as $key => $val) {
            if (isset($_GET[$key])) {
                $arr[$key] = $_GET[$key];
            }
        }

        return $arr;
    }