push-notification

推送通知与后台任务

通知权限

请求时机

• 禁止在 App 启动时立即请求通知权限，应在用户触发相关操作后请求（如完成注册、关注内容后）
• 只请求一次，被拒绝后禁止反复弹窗，引导用户去系统设置开启

权限请求

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

权限检查与引导

func checkNotificationAuthorization() async -> Bool {
    let settings = await UNUserNotificationCenter.current().notificationSettings()
    if settings.authorizationStatus == .denied {
        showSettingsAlert(message: "请在系统设置中开启通知权限")
        return false
    }
    return settings.authorizationStatus == .authorized
}

func showSettingsAlert(message: String) {
    guard let url = URL(string: UIApplication.openSettingsURLString) else { return }
    if UIApplication.shared.canOpenURL(url) {
        UIApplication.shared.open(url)
    }
}

---

APNs 注册与 Token 管理

注册

func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
    let token = deviceToken.map { String(format: "%02x", $0) }.joined()
    TokenStorage.shared.saveAPNsToken(token)
    Task { await sendTokenToBackend(token) }
}

func application(_ application: UIApplication, didFailToRegisterForRemoteNotificationsWithError error: Error) {
    Logger.error("APNs 注册失败: \(error)")
}

Token 管理

• Token 每次安装和系统更新都可能变化，每次启动都必须注册
• Token 发送到后端后本地缓存，下次对比是否变化，变化则重新上报
• 模拟器无法获取 APNs Token，Debug 时需跳过或使用测试 Token

---

本地通知

基本发送

func scheduleLocalNotification(title: String, body: String, in seconds: TimeInterval) {
    let content = UNMutableNotificationContent()
    content.title = title
    content.body = body
    content.sound = .default
    content.badge = NSNumber(value: UIApplication.shared.applicationIconBadgeNumber + 1)

    let trigger = UNTimeIntervalNotificationTrigger(timeInterval: seconds, repeats: false)
    let request = UNNotificationRequest(identifier: UUID().uuidString, content: content, trigger: trigger)

    UNUserNotificationCenter.current().add(request)
}