didUpdateLocations在swift中被多次调用3

问题描述：

didUpdateLocations被调用很多次。所以我如何处理停止这一点。我尝试使用didUpdateLocations中的locationManager.stopUpdatingLocation（），但它不能正常工作。didUpdateLocations在swift中被多次调用3

override func viewDidLoad() 
    { 
    super.viewDidLoad() 
    //for Authorisation from the User. 
    isAuthorizedtoGetUserLocation() 

    if CLLocationManager.locationServicesEnabled() { 
     locationManager.delegate = self 
     locationManager.desiredAccuracy = kCLLocationAccuracyBest 
     locationManager.startUpdatingLocation() 
     } 
    } 

    func isAuthorizedtoGetUserLocation() { 

    if CLLocationManager.authorizationStatus() != .authorizedWhenInUse  { 
     locationManager.requestWhenInUseAuthorization() 
    } 
} 

    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) { 
    locationManager.stopUpdatingLocation() 
     let locValue:CLLocationCoordinate2D = manager.location!.coordinate 
     print("locations = \(locValue.latitude) \(locValue.longitude)") 

     let camera = GMSCameraPosition.camera(withLatitude: locValue.latitude, longitude: locValue.longitude, zoom: 6.0) 
     let mapView = GMSMapView.map(withFrame: CGRect.zero, camera: camera) 
     self.view = mapView 

     // Creates a marker in the center of the map. 
     let marker = GMSMarker() 
     marker.position = CLLocationCoordinate2D(latitude: locValue.latitude, longitude: locValue.longitude) 
     marker.title = "name" 
     marker.map = mapView 

}

Udated代码错误

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

    manager.stopUpdatingLocation() 
    manager = nil // Here it is giving error "Cannot assign to value: 'manager' is a 'let' constant" 

    var newLocation: CLLocation? = locations.last 
    var locationAge: TimeInterval? = -(newLocation?.timestamp.timeIntervalSinceNow)! 
    if Double(locationAge!) > 5.0 { 
     return 
    } 
    if Double((newLocation?.horizontalAccuracy)!) < 0 { 
     return 
    } 


      //manager = nil 
     let locValue:CLLocationCoordinate2D = manager.location!.coordinate 
     print("locations = \(locValue.latitude) \(locValue.longitude)") 

     let camera = GMSCameraPosition.camera(withLatitude: locValue.latitude, longitude: locValue.longitude, zoom: 6.0) 
     let mapView = GMSMapView.map(withFrame: CGRect.zero, camera: camera) 
     self.view = mapView 

     // Creates a marker in the center of the map. 
     let marker = GMSMarker() 
     marker.position = CLLocationCoordinate2D(latitude: locValue.latitude, longitude: locValue.longitude) 
     marker.title = "name" 
     marker.map = mapView 

}

你怎么确定startUpdatingLocation（）被调用一次以上？从代码的外观来看，每次加载视图时只应调用一次。 – dylanthelion

在这种情况下，这是预期的行为。该方法在由您的kCLLocationAccuracy确定的频率上被调用。请参阅@ anbu的答案，了解如何设置它。基本上，准确度越高，代表中调用的方法越频繁，手机使用的功率也越大（GPS可快速消耗电池电量）。 – dylanthelion

答

您需要设置CLLocation经理distanceFilter属性如下：

/* Notify changes when device has moved x meters. 
* Default value is kCLDistanceFilterNone: all movements are reported. 
*/ 
self.locationManager.distanceFilter = 10.0f; // you can change as per your require ment

didUpdateLocations在swift中被多次调用3

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