想要在iOS应用程序中阻止通知，当设备使用Firebase处于锁定状态时？

import Firebase
import UserNotifications

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
    FirebaseApp.configure()
    UNUserNotificationCenter.current().delegate = self
    return true
}

extension AppDelegate: UNUserNotificationCenterDelegate {
    func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
        if UIApplication.shared.applicationState == .inactive || UIApplication.shared.applicationState == .background {
            // 设备处于锁定状态，取消通知显示
            completionHandler([])
        } else {
            // 设备处于活动状态，显示通知
            completionHandler([.alert, .badge, .sound])
        }
    }
}

func registerForPushNotifications() {
    UNUserNotificationCenter.current().requestAuthorization(options: [.alert, .badge, .sound]) { (granted, error) in
        guard granted else { return }
        DispatchQueue.main.async {
            UIApplication.shared.registerForRemoteNotifications()
        }
    }
}