/**
  * {@inheritdoc}
  *
  * Add classes to inputs
  *
  * @param string $fieldName the field name
  * @param array $options The options for the input element
  * @return string The generated input element
  */
 protected function _getInput($fieldName, $options)
 {
     if (in_array($options['type'], array('select', 'url', 'text', 'textarea'))) {
         foreach (explode(' ', $this->config('input_class')) as $class) {
             $options = $this->addClass($options, $class);
         }
     }
     return parent::_getInput($fieldName, $options);
 }