Swift 4 - 更新隐私设置 CLLocationManager 后刷新视图

Question

我正在创建一个基于位置的应用程序，当用户拒绝位置访问时，会弹出一个警告视图，要求用户转到设置页面并更新设置以允许位置访问。如果用户允许访问然后按回键，则视图不会使用允许更新位置的更新设置刷新。

在用户从设置页面返回应用程序后，是否有功能可以运行刷新并开始更新位置。

感谢任何建议或帮助。谢谢。

用户看到提醒：

用户点击返回应用程序后，页面需要刷新以更新地图上的位置：

func alertForNoLocationAccess(){

    let alert = UIAlertController(title: "Allow Location Access", message: "Cannot add location data and map coordinates to your entries without access. Press settings to update or cancel to deny access.", preferredStyle: .alert)

    alert.addAction(UIAlertAction(title: "Settings", style: .default, handler: { action in

        if let url = URL(string:UIApplication.openSettingsURLString) {
            if UIApplication.shared.canOpenURL(url) {
                if #available(iOS 10.0, *) {
                    UIApplication.shared.open(url, options: [:], completionHandler: nil)
                } else {
                    UIApplication.shared.openURL(url)
                }
            }
        }

    }))

    alert.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: nil))

    self.present(alert, animated: true)
}

Answer 1

将 ViewController/AppDelegate 注册到 NotificationCenter 以在用户从 Settings 打开应用程序时收到通知。

NotificationCenter.default.addObserver(self, selector: #selector(willEnterForeground), name: UIApplication.willEnterForegroundNotification, object: nil)

在用户打开应用程序时，再次请求位置更新到 CLLocationManager。如果用户已经接受了请求，那么 CLLocationManager 将开始更新用户的位置而不会中断。

@objc func willEnterForeground() {

    //Register for
    registerForLocationUpdates()
}

func registerForLocationUpdates() {

    self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
    self.locationManager.requestWhenInUseAuthorization()

    if CLLocationManager.locationServicesEnabled() {

        locationManager.delegate = self
        locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters
        locationManager.startUpdatingLocation()
    }
}

Answer 2

查看 Apple 的文档，您会发现：

"When you request authorization, or when your app's authorization status changes, use the locationManager(_:didChangeAuthorization:) method of your delegate object to process the changes. Listing 3 shows an implementation of that method that enables or disables features based on the app's current authorization level."

显然，如果用户决定关闭您获取位置数据的权限，此委托方法也会被触发。

如果您显示此提醒，您还应该使用此通知关闭提醒，以防用户在未使用提醒中的按钮的情况下手动转到“设置”。

Answer 3

实现CLLocationManagerDelegate的Delegate方法

// MARK: - CLLocationManagerDelegate
    extension LocationTracker: CLLocationManagerDelegate {

        func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
            print(locations)
            guard let location = locations.first else { return }
            lastLocation = location
            print(LocationTracker.shared.lastLocation)
            print("location = \(location.coordinate.latitude) \(location.coordinate.longitude)")
            locateMeCallback?(location)
        }

        func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
            print(error.localizedDescription)
        }

        func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
            enableLocationServices()
        }

    }

/// enableLocationService 是这样的

func enableMyAlwaysFeatures() {
        locationManager.allowsBackgroundLocationUpdates = true
        locationManager.pausesLocationUpdatesAutomatically = true
        locationManager.startUpdatingLocation()
        locationManager.delegate = self
    }

Swift 4 - 更新隐私设置 CLLocationManager 后刷新视图

Swift 4 - Refresh View after updating privacy settings CLLocationManager

cllocationmanager

ios

swift