iBeacon、iOS13、BGAppRefreshTask

Question

我需要实现在后台检测iBeacons每例如5分钟，为此，我想使用新的苹果框架BackgroundTask

下面是我实现我的操作子类的方式

import CoreLocation

class BeaconsRecord: AsyncOperation {

    private let locationManager: CLLocationManager
    private let clBeaconIdentityConstraint: CLBeaconIdentityConstraint
    var beacons = [CLBeacon]()

    init (locationManager: CLLocationManager, uuid: UUID) {
        self.locationManager = locationManager
        self.clBeaconIdentityConstraint = CLBeaconIdentityConstraint(uuid: uuid)
        super.init()
    }

    override func main() {
        locationManager.delegate = self
        locationManager.startRangingBeacons(satisfying: clBeaconIdentityConstraint)
    }
}

extension BeaconsRecord: CLLocationManagerDelegate {

    func locationManager(_ manager: CLLocationManager, didRangeBeacons beacons: [CLBeacon], in region: CLBeaconRegion) {
        self.locationManager.stopRangingBeacons(satisfying: clBeaconIdentityConstraint)
        self.beacons = beacons
        self.state = .Finished
    }
}

如果我在前台使用它工作得很好，那么我会尝试在后台使用它，就像在wwdc演示文稿中显示的那样，它不工作。我怀念的吗？我的appdelegate实现

@UIApplicationMain类AppDelegate: UIResponder，UIApplicationDelegate {

var window: UIWindow?
var locationManager : CLLocationManager?
let uuid = UUID(uuidString: "B9407F30-F5F8-466E-AFF9-25556B57FE6D")!

lazy var detectBeaconsQueue : OperationQueue = {
    var queue = OperationQueue()
    queue.name = "detectBeaconsQueue"
    queue.maxConcurrentOperationCount = 1
    return queue
}()

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
    // Override point for customization after application launch.
    locationManager = CLLocationManager()
    locationManager?.requestAlwaysAuthorization()

    registerBackgroundTaks()
    registerLocalNotification()

    return true
}

//MARK: Register BackGround Tasks
func registerBackgroundTaks() {
    BGTaskScheduler.shared.register(forTaskWithIdentifier: "xxx.xxxxxx.xxxxxxxxxxx", using: nil) { task in
         self.scheduleLocalNotification()
         self.handleAppRefresh(task: task as! BGAppRefreshTask)
      }
}

func applicationDidEnterBackground(_ application: UIApplication) {
    cancelAllPendingBGTask()
    scheduleAppRefresh()
}

}

扩展AppDelegate {

func cancelAllPendingBGTask() {
    BGTaskScheduler.shared.cancelAllTaskRequests()
}

func scheduleAppRefresh() {
       let request = BGAppRefreshTaskRequest(identifier: ""xxx.xxxxxx.xxxxxxxxxxx"")

       // Fetch no earlier than 1 minutes from now
    request.earliestBeginDate = Date(timeIntervalSinceNow: 1 * 60)
       do {
          try BGTaskScheduler.shared.submit(request)
       } catch {
          print("Could not schedule app refresh: \(error)")
       }
    }

func handleAppRefresh(task: BGAppRefreshTask) {
    // Schedule a new refresh task
    scheduleAppRefresh()

    let operation = BeaconsRecord(locationManager: locationManager!,
                                  uuid: uuid)

    task.expirationHandler = {
        operation.cancel()
    }

    operation.completionBlock = {
        task.setTaskCompleted(success: !operation.isCancelled)
    }

    detectBeaconsQueue.addOperation(operation)
}

}

Answer 1

在基于信标的项目工作了两年之后，我可以说，没有办法在后台检测iBeacon，特别是在你的场景中。

在iOS后台，任务将在3分钟后终止如果您开始后台确定任务，以节省电池。唯一的办法是，在信标测距模式下工作app时，可以每5分钟调用一次线程来确定信标的最后状态，而不会终止应用程序。屏幕可以关闭，但应用程序仍必须正常工作。但这不是合法的情况。审查团队不会因为保护用户利益而批准你的应用程序。

在后台的信标监控没有问题，，但您只能知道信标信号是否仍与设备连接，或在30秒内未连接。

您必须深入了解监控和区域扫描之间的区别。在这种情况下，如果您的方案不是从Background Monitoring应用的，则无法使用信标测距每隔5分钟确定后台的信标状态。

有关更多信息，请阅读：https://community.estimote.com/hc/en-us/articles/203914068-Is-it-possible-to-use-beacon-ranging-in-the-background-