2017-03-04 91 views
0

didUpdateLocations被調用很多次。所以我如何處理停止這一點。我嘗試使用didUpdateLocations中的locationManager.stopUpdatingLocation(),但它不能正常工作。didUpdateLocations在swift中被多次調用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代碼錯誤

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 

} 
+1

你怎麼確定startUpdatingLocation()被調用一次以上?從代碼的外觀來看,每次加載視圖時只應調用一次。 – dylanthelion

+0

在這種情況下,這是預期的行爲。該方法在由您的kCLLocationAccuracy確定的頻率上被調用。請參閱@ anbu的答案,瞭解如何設置它。基本上,準確度越高,代表中調用的方法越頻繁,手機使用的功率也越大(GPS可快速消耗電池電量)。 – dylanthelion

回答

1

您需要設置CLLocation經理distanceFilter屬性如下:

/* 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