public function post_write_settings($original) {
        // Comparison must work for arrays too.
        if (serialize($original) === serialize($this->get_setting())) {
            return false;
        }

        $callbackfunction = $this->updatedcallback;
        if (!empty($callbackfunction) and is_callable($callbackfunction)) {
            $callbackfunction($this->get_full_name());
        }
        return true;
    }