public function getRenderPublicField($key, $field = null, $load_value = true)
    {
        $class = get_called_class();
        if ($key === self::KEY_CLASS) {
            $attribs = array('type'=>'hidden', 'name'=>$key, 'value'=>$class);
            return Html::tag('input', null, $attribs);
        }
        if ($key === self::KEY_NONCE) {
            $attribs = array('type'=>'hidden', 'name'=>$key, 'value'=>wp_create_nonce($this->getNonceAction()));
            return Html::tag('input', null, $attribs);
        }

        if ($load_value) {
            if (!is_array($field)) {
                $field = self::getField($key);
            }
            if (!array_key_exists('value', $field)) {
                $field['value'] = $this->$key;
            }
        }
        return self::getRenderMetaBoxField($key, $field);
    }