public function getSetting($setting_key, $focus = null, $user = null)
    {
        $params = array();
        $params['setting_key'] = $setting_key;

        if ($focus) {
            $params['focus'] = $focus;
        }

        if ($user) {
            $params['user'] = $user;
        }

        $setting = $this->findOneBy($params);

        if ($setting) {
            return $setting->getValue();
        }

        return null;
    }