tvOS 中的 CloudKit 订阅

Question

我正在尝试使用 CloudKit 和 CKSubcription 在几台 Apple TV 之间同步数据。问题是当我添加、删除或更新记录时，永远不会调用 application:didReceiveRemoteNotification:。我相信我正确配置了订阅，并且我已经确认它们已添加到 CloudKit 仪表板。我曾多次尝试在仪表板中重置开发环境，但这无济于事。我真的不想创建一个计时器来经常获取。感谢您的帮助！

另外，如果重要的话，我使用的是 CloudKit 中的私有数据库而不是公共数据库。

这是我的代码：

AppDelegate.swift

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

    CloudKitManager.subscribeToItemUpdates()
    application.registerForRemoteNotifications()

    ...

    return true
}

CloudKitManager.swift

class func subscribeToItemUpdates() {

    if let uuid = UIDevice.currentDevice().identifierForVendor?.UUIDString {

        saveSubscriptionWithIdentifier(uuid + "create", options: CKSubscriptionOptions.FiresOnRecordCreation)
        saveSubscriptionWithIdentifier(uuid + "update", options: CKSubscriptionOptions.FiresOnRecordUpdate)
        saveSubscriptionWithIdentifier(uuid + "delete", options: CKSubscriptionOptions.FiresOnRecordDeletion)
    }

}

class func saveSubscriptionWithIdentifier(identifier: String, options: CKSubscriptionOptions) {

    let sub = CKSubscription(recordType: "Message", predicate: NSPredicate(value: true), subscriptionID: identifier, options: options)
    sub.notificationInfo = CKNotificationInfo()

    let publicDatabase = CKContainer.defaultContainer().publicCloudDatabase
        publicDatabase.saveSubscription(sub) { (savedSubscription, error) -> Void in
        if error != nil {
            print("Error saving CloudKit subscription \(error)")
        }
        else {
            print("Saved subscription to CloudKit", savedSubscription)
        }
    }
}

Answer 1

tvOS 和 iOS 之间存在细微差别。在我的演示应用程序中，我这样处理它：

#if os(tvOS)
//This will only be called when your app is active. So this is what you should use on tvOS
func application(application: UIApplication, didReceiveRemoteNotification userInfo: [NSObject : AnyObject]) {
    EVLog("Push received")
    EVCloudData.publicDB.didReceiveRemoteNotification(userInfo, executeIfNonQuery: {
        EVLog("Not a CloudKit Query notification.")
    }, completed: {
        EVLog("All notifications are processed")
    })
}
#else
// Process al notifications even if we are in the background. tvOS will not have this event
// Make sure you enable background notifications in the app settings. (entitlements: pushnotifications and  backgrounds modes - notifications plus background fetch)
func application(application: UIApplication, didReceiveRemoteNotification userInfo: [NSObject : AnyObject], fetchCompletionHandler completionHandler: (UIBackgroundFetchResult) -> Void) {
    EVLog("Push received")
    EVCloudData.publicDB.didReceiveRemoteNotification(userInfo, executeIfNonQuery: {
        EVLog("Not a CloudKit Query notification.")
    }, completed: {
        EVLog("All notifications are processed")
        completionHandler(.NewData)
    })
}
#endif

欲了解更多信息，请参阅EVCloudKitDao