yii2怎么自适应切换模板

// frontend/behaviors/MobileBehavior.php
class MobileBehavior extends \yii\base\Behavior{    public function events()
        {            return [
                    \yii\web\Controller::EVENT_BEFORE_ACTION => 'beforeAction'
                ];
        }        public function beforeAction($event)
        {            if (strpos($_SERVER['HTTP_USER_AGENT'], 'iPhone') || strpos($_SERVER['HTTP_USER_AGENT'], 'Android') {
                    $event->sender->module->setViewPath($event->sender->module->getBasePath().DIRECTORY_SEPARATOR.'H5Views');
                } 
        }
}

/ frontend/controllers/BaseController.php
class BaseController extends \yii\web\Controller{    public function behaviors()
        {            return [
                    \frontend\behaviors\MobileBehavior::className()
                ];
        }        // 其他action}