ios - startMonitoringSignificantLocationChange 不会调用 didUpdateLocations

Question

我尝试使用 GoogleMap SDK 记录用户正在走的路径。我正在使用折线在 map 上绘制线条，以向用户显示所采取的路径。为了减少生成的坐标并使线条看起来干净(而不是看起来弯曲)，我调用 CLLocationManger 的 startMonitoringSignificantChange 而不是 startUpdatingLocation。然而，这似乎不起作用。当 View 加载时，它只调用一次 didUpdateLocations 方法，但之后，它就停止调用。我哪里做错了？

这是我的代码

    override func viewDidLoad() {
        super.viewDidLoad()
        locationManager.delegate = self
        locationManager.desiredAccuracy = kCLLocationAccuracyHundredMeters
        locationManager.requestAlwaysAuthorization()

        locationManager.startMonitoringSignificantLocationChanges()

    }

    extension LocationViewController: CLLocationManagerDelegate {

        func locationManager(manager: CLLocationManager, didChangeAuthorizationStatus status: CLAuthorizationStatus) {
            if status == .AuthorizedAlways {
                locationManager.startMonitoringSignificantLocationChanges()
                mapView.myLocationEnabled = true
                mapView.settings.myLocationButton = true
            }
        }

        func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {

            if let location = manager.location {

                    path.addCoordinate(CLLocationCoordinate2D(latitude: location.coordinate.latitude,
                        longitude: location.coordinate.longitude))
                    let polyline = GMSPolyline(path: path)
                    polyline.strokeColor = UIColor.redColor()
                    polyline.strokeWidth = 3
                    polyline.geodesic = true
                    polyline.map = mapView

                    // Save the coordinates to array
                    coordinateArray.append([location.coordinate.latitude, location.coordinate.longitude])



                }


            }

        }
    }

Answer 1

在locationManager.requestAlwaysAuthorization()后添加以下代码行

locationManager.allowsBackgroundLocationUpdates = true
locationManager.pausesLocationUpdatesAutomatically = false

附:如果您的 View 持有 locationManager 实例，则在卸载 View 后它可能不会收到位置更新。您可以删除以下行，因为它对于重要位置更新没有用:

locationManager.desiredAccuracy = kCLLocationAccuracyHundredMeters