ios - 应用程序从后台返回后位置不会更新

Question

我正在构建一个应用程序，我希望每当应用程序从后台返回时跟踪更新的用户位置。

我在 AppDelegate 的 didFinishLaunchingWithOptions 方法中编写了位置跟踪代码

//Core Location Administration
locationManager.desiredAccuracy = kCLLocationAccuracyBest
locationManager.distanceFilter = 70
locationManager.requestAlwaysAuthorization()
locationManager.pausesLocationUpdatesAutomatically = false
locationManager.startMonitoringVisits()
locationManager.delegate = self

由于我无法验证访问，因此我也添加了标准位置跟踪

locationManager.allowsBackgroundLocationUpdates = true
locationManager.startUpdatingLocation()

我创建了 CLLocationManagerDelegate block 并添加了以下代码

extension AppDelegate: CLLocationManagerDelegate {
    func locationManager(_ manager: CLLocationManager, didVisit visit: CLVisit) {
        let clLocation = CLLocation(latitude: visit.coordinate.latitude, longitude: visit.coordinate.longitude)

        // Get location description
        AppDelegate.geoCoder.reverseGeocodeLocation(clLocation) { placemarks, _ in
            if let place = placemarks?.first {
                let description = "\(place)"
                self.newVisitReceived(visit, description: description)
            }
        }
    }

    func newVisitReceived(_ visit: CLVisit, description: String) {
        let location = Location(visit: visit, descriptionString: description)
        LErrorHandler.shared.logInfo("\(location.latitude), \(location.longitude)")
        UserModal.shared.setUserLocation(location)
        UserModal.shared.userLocationUpdated = Date()
    }

    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        guard let location = locations.first  else {
            return
        }

        locationManager.stopUpdatingLocation()

        let uL = Location(location:location.coordinate, descriptionString: "")
        LErrorHandler.shared.logInfo("\(uL.latitude), \(uL.longitude)")
        UserModal.shared.setUserLocation(uL)
        UserModal.shared.userLocationUpdated = Date()
    }
}

我添加了此代码以在应用程序进入前台时开始位置跟踪

func applicationWillEnterForeground(_ application: UIApplication) {
        // Called as part of the transition from the background to the active state; here you can undo many of the changes made on entering the background.
        locationManager.startUpdatingLocation()
    }

如果我在 ViewController 上并且应用程序返回到后台，那么当应用程序进入前台时，它不会刷新位置。

有人可以建议更好的方法吗？

Answer 1

您应该在应用程序委托(delegate)的 didbecomeActive 方法中编写位置代码，而不是在 didFinishLaunchingWithOptions 中。尝试一下希望它会有所帮助。