ios - 在 iOS 13.0 及更高版本中，后台计时器在 30 秒后不工作。有什么解决办法吗？

Question

我有一个包含计时器功能的 iOS 应用程序。应用程序在前台运行时完全正常，计时器运行良好。但是当我进入后台模式时，计时器仅工作 30 秒，并且出现“不存在标识符错误的后台任务”。我的应用程序中启用了后台模式和后台处理功能有解决方案吗？

**:SOLUTION WORKING:**

On Location Updates in Background Modes from capabilities

    Put below code in your viewcontroller where timer is running

    var locationManager = CLLocationManager()

    CLLocationManagerDelegate

    if (CLLocationManager.locationServicesEnabled())
            {
                self.locationManager = CLLocationManager()
                self.locationManager.delegate = self
                self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
                self.locationManager.requestAlwaysAuthorization()
                self.locationManager.startUpdatingLocation()
                self.locationManager.allowsBackgroundLocationUpdates = true
                self.locationManager.pausesLocationUpdatesAutomatically = false
            }
            backgroundTaskIdentifier = UIApplication.shared.beginBackgroundTask(expirationHandler: {
                UIApplication.shared.endBackgroundTask(self.backgroundTaskIdentifier!)
            })


    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
            let location = locations.last! as CLLocation
        let center = CLLocationCoordinate2D(latitude: location.coordinate.latitude, longitude: location.coordinate.longitude)
            _ = MKCoordinateRegion(center: center, span: MKCoordinateSpan(latitudeDelta: 0.01, longitudeDelta: 0.01))
        }