protected function genericHandle($dataFormatterClass, $ext, GridField $gridField, $request = null)
    {
        $items = $this->getItems($gridField);

        $this->setHeader($gridField, $ext);


        $formater = new $dataFormatterClass();
        $formater->setUseLabelsAsHeaders($this->useLabelsAsHeaders);

        $fileData = $formater->convertDataObjectSet($items);

        return $fileData;
    }