public function addDataProviderInput()
    {
        $input = (new Select(self::DATA_PARAM))
                ->setOptions(array(null => '---'));
        $dataProviderClasses = array();
        foreach ($this->di->get('config')->formFactory->dataProviders as $classname) {
            $provider = new $classname;
            if ($provider instanceof DataProviderInterface) {
                $dataProviderClasses[$classname] = $provider->getName();
            }
        }
        $input
                ->addOptions($dataProviderClasses)
                ->setLabel('Data provider');
        $this->add($input);
    }