protected function renderFields(array $fields)
    {
        $output = '';
        foreach ($fields as $id => $field) {
            // Add defaults.
            $field += array(
                'id' => $id,
                'name' => $id,
                'label' => '',
                'value' => '',
                'description' => '',
                'attributes' => array(),
                'options' => array(),
            );
            $output .= $this->renderField($field);
        }
        return $output;
    }