无法从Firebase 3.2.0主题接收iOS上的推送通知

Question

我在https://firebase.google.com/docs/notifications/ios/console-topics#receive_and_handle_topic_messages上按照谷歌的教程来订阅我的iOS应用上的Firebase主题.

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject : AnyObject]?) -> Bool {

    FIRMessaging.messaging().subscribeToTopic("/topics/Notifications")

    let homeViewController = UINavigationController(rootViewController: HomeViewController())

    UINavigationBar.appearance().translucent = false
    window = UIWindow(frame: UIScreen.mainScreen().bounds)
    window?.rootViewController = homeViewController

    window?.makeKeyAndVisible()
    return true
}

但是,当我从Firebase控制台发送主题推送通知时.我无法收到任何推送通知.但是当我从控制台向用户段发送推送通知时,推送工作正常.当我检查Xcode控制台时,我看到了这个FIRMessaging错误.

2016-05-31 11:11:47.893: <FIRMessaging/WARNING> Cannot subscribe to topic: /topics/Notifications with token: (null) 

我试图搜索这个错误,但没有找到任何运气.我不确定这是否是导致我的应用程序无法接收任何主题推送的问题.

有没有人有这个问题,知道如何解决它？

Answer 1

看起来好像你打电话subscribeToTopic太早了.

首先,在设置任何Firebase呼叫之前,请务必致电

FIRApp.configure()

这将确保正确设置和初始化所有Firebase服务.

接下来,您需要稍等一下才能订阅主题.您的客户需要首先使用APN和FCM注册您的应用程序,以确保它可以接收通知.这涉及网络呼叫,这意味着您无法在应用首次启动时订阅主题.

相反,我建议将该代码放入您的application:didRegisterUserNotificationSettings处理程序中.像这样的东西:

- (void)application:(UIApplication *)application didRegisterUserNotificationSettings:(UIUserNotificationSettings *)notificationSettings {
  NSLog(@"Hooray! I'm registered!");
  [[FIRMessaging messaging] subscribeToTopic:@"/topics/cool_users"];
}

编辑:和Swift版本......

func application(application: UIApplication, didRegisterUserNotificationSettings notificationSettings: UIUserNotificationSettings) {
  print("Hooray! I'm registered!")
  FIRMessaging.messaging().subscribeToTopic("/topics/swift_fans")
}

Answer 2

该接受的解决方案并没有为我工作.application:didRegisterUserNotificationSettings:调用时令牌并不总是可用.例如,如果应用程序是新安装的并且第一次启动则FIRInstanceID.instanceID().token()返回nil.

您需要在令牌可用subscribeToTopic: 后确保应用程序调用.我最终创建了一个辅助对象,它在令牌到达后以FIFO顺序排队subscribeToTopic:,unsubscribeFrom:调用和执行它们.

class FIRMessagingHelper {

    private let queue: OperationQueue

    init() {
        queue = OperationQueue()
        queue.maxConcurrentOperationCount = 1
        queue.addOperation(TokenReadyOperation())
    }

    func subscribeTo(topic: String) {
        queue.addOperation { 
            OperationQueue.main.addOperation({ 
                FIRMessaging.messaging().subscribeToTopic(topic)
            })
        }
    }

    func unsubscribeFrom(topic: String) {
        queue.addOperation {
            OperationQueue.main.addOperation({
                FIRMessaging.messaging().unsubscribeFromTopic(topic)
            })
        }
    }
}

TokenReadyOperation等待,直到出现令牌.AsynchronousOperation用作最小化样板的基类.

class TokenReadyOperation : AsynchronousOperation {

    override init() {
        super.init()
        NotificationCenter.default.addObserver(self,
                                               selector: #selector(TokenReadyOperation.tokenRefreshed(notification:)),
                                               name: .firInstanceIDTokenRefresh,
                                               object: nil)
    }

    override func didStart() {
        finishIfTokenAvailable()
    }

    private func finishIfTokenAvailable() {
        guard FIRInstanceID.instanceID().token() != nil else { return }
        markFinished()
    }

    /// Posted every time token changes
    @objc private func tokenRefreshed(notification: Notification) {
        finishIfTokenAvailable()
    }
}

要记住几件事:

• 应用程序必须致电FIRApp.configure()或FIRApp.configureWithOptions(_:)事先进行任何Firebase呼叫(如Todd Kerpelman所述)
• subscribeToTopic:,unsubscribeFrom:不是线程安全的,必须在主线程上执行
• 主题名称必须采用"/ topics/*"格式(如henmer所述)
• 确保使用不同的配置plist进行应用程序的调试和App Store发布.见FIRApp.configureWithOptions(_:)文档.
• 日期和时间应该是最新的,否则可能无法交付令牌.
• 确保使用最新的框架版本.2017年1月左右发布的SDK发布了通知问题.