我正在從 Symfony 上的偵聽器發送郵件（Swift 郵件程序），只有在使用 renderView 時出現錯誤（也嘗試使用 render）...未定義的方法“renderView”。這是我的聽眾：<?phpnamespace App\Events;use ApiPlatform\Core\EventListener\EventPriorities;use App\Entity\User;use Symfony\Component\EventDispatcher\EventSubscriberInterface;use Symfony\Component\HttpFoundation\Request;use Symfony\Component\HttpKernel\Event\ViewEvent;use Symfony\Component\HttpKernel\KernelEvents;class UserSubscriber implements EventSubscriberInterface {    private $mailer;    public function __construct(\Swift_Mailer $mailer)    {        $this->mailer = $mailer;    }    public static function getSubscribedEvents()    {        return [            KernelEvents::VIEW => ['sendMail', EventPriorities::POST_VALIDATE],        ];    }    public function sendMail(ViewEvent $event): void    {        $user = $event->getControllerResult();        $method = $event->getRequest()->getMethod();        if (!$user instanceof User || Request::METHOD_POST !== $method) {            return;        }        $message = (new \Swift_Message('A new book has been added'))            ->setFrom('[email protected]')            ->setTo('[email protected]')            ->setBody(                $this->renderView(                    // templates/emails/registration.html.twig                    'emails/registration.html.twig',                    ['userPseudo' => $user->getPseudo()]                ),                'text/html'            );        $this->mailer->send($message);    }}我知道模板服務在偵聽器中不可用，但我不明白如何注入它。