ios - 仅显示一个位置权限警报

Question

我希望我的应用程序在活动和后台模式下定位（如果仅使用NSLocationAlwaysUsageDescription权限，则不显示myLocationButton ）。我在 Info.plist 中设置：

<key>NSLocationAlwaysUsageDescription</key>
<string>$(PRODUCT_NAME) location use</string>
<key>NSLocationWhenInUseUsageDescription</key>
<string>$(PRODUCT_NAME) location use</string>
<key>UIBackgroundModes</key>

并添加 MapViewController

self.locationManager.requestWhenInUseAuthorization()
self.locationManager.requestAlwaysAuthorization()

但是应用启动时，只显示第一个Location权限提示，重新打开应用后出现第二个权限提示。

更新：

override func viewDidLoad() {
        super.viewDidLoad()
 ...    
 locationManager.delegate = self
 locationManager.requestWhenInUseAuthorization()
 viewMap.addObserver(self, forKeyPath: "myLocation", options: NSKeyValueObservingOptions.new, context: nil)
        self.startLocationUpdates()
 ...
}

func startLocationUpdates() {
    self.locationManager.delegate = self
    self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
    self.locationManager.activityType = CLActivityType.automotiveNavigation
    self.locationManager.distanceFilter = distanceFilterMetr
    self.locationManager.requestAlwaysAuthorization()
    self.locationManager.startUpdatingLocation()
}

override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {

        let myLocation: CLLocation = change?[NSKeyValueChangeKey.newKey] as! CLLocation
        viewMap.camera = GMSCameraPosition.camera(withTarget: myLocation.coordinate, zoom: observeZoom)
        mapRoute.coordinateLatitude = myLocation.coordinate.latitude
        mapRoute.coordinateLongitude = myLocation.coordinate.longitude
        viewMap.delegate = self
        viewMap.settings.myLocationButton = true
        viewMap.settings.compassButton = true
        didFindMyLocation = true
}

Answer 1

在您的课程中添加此委托：

CLLocationManagerDelegate

现在在你的课堂上：

var locationManager:CLLocationManager!
var map = GMSMapView()
var currentLatitude:Double!
var currentLongitude:Double!

之后在你的代码中添加这个：

override func loadView() {

    print("loadView called")

    // Enable some map settings

    map.isMyLocationEnabled = true
    map.settings.myLocationButton = true
    map.settings.compassButton = true
    map.settings.scrollGestures = true
    map.settings.zoomGestures = true
    map.delegate = self

    view = map
}

override func viewDidLoad() {

    super.viewDidLoad()

    print("ViewDidLoad called")

    // Configuring location manager.

    locationManager = CLLocationManager()
    locationManager.delegate = self
    locationManager.requestAlwaysAuthorization()
    locationManager.desiredAccuracy = kCLLocationAccuracyBest
    locationManager.startUpdatingLocation()
    locationManager.startMonitoringSignificantLocationChanges()
}

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

    print("locationManager function called")

    // Fetch current location coordinates

    let locValue:CLLocationCoordinate2D = (locationManager.location?.coordinate)!
    currentLatitude = locValue.latitude
    currentLongitude = locValue.longitude
    print("Current Location = \(currentLatitude!), \(currentLongitude!)")

    // Zoom to current location

    let target = CLLocationCoordinate2D(latitude: currentLatitude!, longitude: currentLongitude!)
    map.camera = GMSCameraPosition.camera(withTarget: target, zoom: 17)

    locationManager.stopUpdatingLocation()

}

添加此代码后，右键单击您的 Info.plist 和“作为源代码打开”。将此添加到您的 Info.plist 中。

<key>LSApplicationQueriesSchemes</key>
<array>
    <string>googlechromes</string>
    <string>comgooglemaps</string>
</array>
<key>LSRequiresIPhoneOS</key>
<true/>
<key>NSBluetoothPeripheralUsageDescription</key>
<string></string>
<key>NSCameraUsageDescription</key>
<string></string>
<key>NSContactsUsageDescription</key>
<string></string>
<key>NSLocationUsageDescription</key>
<string></string>
<key>NSLocationWhenInUseUsageDescription</key>
<string></string>
<key>NSLocationAlwaysUsageDescription</key>
<string></string>
<key>NSMicrophoneUsageDescription</key>
<string></string>
<key>NSMotionUsageDescription</key>
<string></string>
<key>NSPhotoLibraryUsageDescription</key>
<string></string>
<key>NSRemindersUsageDescription</key>
<string></string>
<key>NSSiriUsageDescription</key>
<string></string>
<key>NSSpeechRecognitionUsageDescription</key>
<string></string>
<key>NSVideoSubscriberAccountUsageDescription</key>
<string></string>