public static function enumTypes() {
        return [
            ButtonInterface::BUTTON_TYPE_DANGER,
            ButtonInterface::BUTTON_TYPE_DEFAULT,
            ButtonInterface::BUTTON_TYPE_INFO,
            ButtonInterface::BUTTON_TYPE_LINK,
            ButtonInterface::BUTTON_TYPE_PRIMARY,
            ButtonInterface::BUTTON_TYPE_SUCCESS,
            ButtonInterface::BUTTON_TYPE_WARNING,
        ];
    }