¿Cómo recuperar el nombre de la ciudad actual del usuario?

¿Cómo recupera el nombre de la ciudad actual del usuario?

Lo que tienes que hacer es configurar una CLLocationManagerque encuentre tus coordenadas actuales. Con las coordenadas actuales que necesita usar MKReverseGeoCoderpara encontrar su ubicación.

- (void)viewDidLoad 
{  
    // this creates the CCLocationManager that will find your current location
    CLLocationManager *locationManager = [[[CLLocationManager alloc] init] autorelease];
    locationManager.delegate = self;
    locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters;
    [locationManager startUpdatingLocation];
}

// this delegate is called when the app successfully finds your current location
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation 
{
    // this creates a MKReverseGeocoder to find a placemark using the found coordinates
    MKReverseGeocoder *geoCoder = [[MKReverseGeocoder alloc] initWithCoordinate:newLocation.coordinate];
    geoCoder.delegate = self;
    [geoCoder start];
}

// this delegate method is called if an error occurs in locating your current location
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error 
{
 NSLog(@"locationManager:%@ didFailWithError:%@", manager, error);
}

// this delegate is called when the reverseGeocoder finds a placemark
- (void)reverseGeocoder:(MKReverseGeocoder *)geocoder didFindPlacemark:(MKPlacemark *)placemark
{
    MKPlacemark * myPlacemark = placemark;
    // with the placemark you can now retrieve the city name
    NSString *city = [myPlacemark.addressDictionary objectForKey:(NSString*) kABPersonAddressCityKey];
}

// this delegate is called when the reversegeocoder fails to find a placemark
- (void)reverseGeocoder:(MKReverseGeocoder *)geocoder didFailWithError:(NSError *)error
{
    NSLog(@"reverseGeocoder:%@ didFailWithError:%@", geocoder, error);
}

¡A partir de iOS 5 MKReverseGeoCoderestá obsoleto!

Así que quieres usarlo CLGeocodercon CLLocationManager, muy simple y funciona con block.

Ejemplo:

- (void)locationManager:(CLLocationManager *)manager
    didUpdateToLocation:(CLLocation *)newLocation
           fromLocation:(CLLocation *)oldLocation
{
   [self.locationManager stopUpdatingLocation];

   CLGeocoder * geoCoder = [[CLGeocoder alloc] init];
    [geoCoder reverseGeocodeLocation:newLocation
                   completionHandler:^(NSArray *placemarks, NSError *error) {
                       for (CLPlacemark *placemark in placemarks) {
                           .... = [placemark locality];
                       }
                   }];
}

Editar: en lugar de un for inbucle, también puede hacer:

NSString *locString = placemarks.count ? [placemarks.firstObject locality] : @"Not Found";

Esto está funcionando bien para mí:

CLGeocoder *geocoder = [[CLGeocoder alloc] init] ;
[geocoder reverseGeocodeLocation:self.locationManager.location
               completionHandler:^(NSArray *placemarks, NSError *error) {
                   NSLog(@"reverseGeocodeLocation:completionHandler: Completion Handler called!");

                   if (error){
                       NSLog(@"Geocode failed with error: %@", error);
                       return;

                   }


                   CLPlacemark *placemark = [placemarks objectAtIndex:0];

                   NSLog(@"placemark.ISOcountryCode %@",placemark.ISOcountryCode);
                   NSLog(@"placemark.country %@",placemark.country);
                   NSLog(@"placemark.postalCode %@",placemark.postalCode);
                   NSLog(@"placemark.administrativeArea %@",placemark.administrativeArea);
                   NSLog(@"placemark.locality %@",placemark.locality);
                   NSLog(@"placemark.subLocality %@",placemark.subLocality);
                   NSLog(@"placemark.subThoroughfare %@",placemark.subThoroughfare);

               }];

Si alguien está intentando pasar a CLGeocoder desde MKReverseGeocoder, entonces he escrito una publicación de blog que podría ser de ayuda http://jonathanfield.me/jons-blog/clgeocoder-example.html

Básicamente, un ejemplo sería, después de haber creado los objetos locationManager y CLGeocoder, simplemente agregue este código a su viewDidLoad () y luego cree algunas etiquetas o áreas de texto para mostrar los datos.

  [super viewDidLoad];
    locationManager.delegate = self;
    [locationManager startUpdatingLocation];

    locationManager.desiredAccuracy = kCLLocationAccuracyBestForNavigation;
    [self.CLGeocoder reverseGeocodeLocation: locationManager.location completionHandler: 
     ^(NSArray *placemarks, NSError *error) {


         CLPlacemark *placemark = [placemarks objectAtIndex:0];


             isoCountryCode.text = placemark.ISOcountryCode;
             country.text = placemark.country;
             postalCode.text= placemark.postalCode;
             adminArea.text=placemark.administrativeArea;
             subAdminArea.text=placemark.subAdministrativeArea;
             locality.text=placemark.locality;
             subLocality.text=placemark.subLocality;
             thoroughfare.text=placemark.thoroughfare;
             subThoroughfare.text=placemark.subThoroughfare;
             //region.text=placemark.region;



     }];

Si alguien lo necesita en Swift 3 , así es como lo hice:

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

    let location = locations.first!
    let coordinateRegion = MKCoordinateRegionMakeWithDistance(location.coordinate, 500, 500)

    self.location = location
    self.locationManager?.stopUpdatingLocation()

    // Drop a pin at user's Current Location
    let myAnnotation: MKPointAnnotation = CustomPointAnnotation()
    myAnnotation.coordinate = CLLocationCoordinate2DMake(location.coordinate.latitude, location.coordinate.longitude)
    myAnnotation.title = "Localização"
    self.mapViewMK.addAnnotation(myAnnotation)

    self.mapViewMK.setRegion(coordinateRegion, animated: true)
    self.locationManager?.stopUpdatingLocation()
    self.locationManager = nil

    // Get user's current location name
    let geocoder = CLGeocoder()
    geocoder.reverseGeocodeLocation(self.location!) { (placemarksArray, error) in

        if (placemarksArray?.count)! > 0 {

            let placemark = placemarksArray?.first
            let number = placemark!.subThoroughfare
            let bairro = placemark!.subLocality
            let street = placemark!.thoroughfare

            self.addressLabel.text = "\(street!), \(number!) - \(bairro!)"
        }
    }
}

Después de configurar CLLocationManager, obtendría la actualización de la ubicación como un par de latitud / longitud. Luego, podría usar CLGeocoder para convertir las coordenadas en un nombre de lugar fácil de usar.

Aquí está el código de muestra en Swift 4 .

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    if let lastLocation = locations.last {
        let geocoder = CLGeocoder()

        geocoder.reverseGeocodeLocation(lastLocation) { [weak self] (placemarks, error) in
            if error == nil {
                if let firstLocation = placemarks?[0],
                    let cityName = firstLocation.locality { // get the city name
                    self?.locationManager.stopUpdatingLocation()
                }
            }
        }
    }
}

Debe obtener la ubicación actual del usuario y luego usar MKReverseGeocoder para reconocer la ciudad.

Hay un gran ejemplo en la Guía de programación de aplicaciones para iPhone , capítulo 8. Una vez que tenga la ubicación, inicialice el geocodificador, configure el delegado y lea el país en la marca de posición. Lea la documentación de MKReverseGeocodeDelegate y cree métodos:

• reverseGeocoder: didFindPlacemark:

• reverseGeocoder: didFailWithError:

  MKReverseGeocoder *geocoder = [[MKReverseGeocoder alloc] initWithCoordinate:newLocation.coordinate];
  geocoder.delegate = self;
  [geocoder start];
  

Puede utilizar este código para obtener la ciudad actual: -

extensión YourController: CLLocationManagerDelegate {func locationManager (administrador: CLLocationManager, ubicaciones didUpdateLocations: [CLLocation]) {

    CLGeocoder().reverseGeocodeLocation(manager.location!, completionHandler: {(placemarks, error)->Void in

        if (error != nil)
        {
            manager.stopUpdatingLocation()
            return
        }
        else
        {
            if placemarks!.count > 0
            {
                let placeMarksArrray: NSArray = placemarks!
                let pm = placeMarksArrray[0] as! CLPlacemark
                self.displayLocationInfo(pm)
                manager.stopUpdatingLocation()
            } else
            {
                print("Problem with the data received from geocoder")
            }
        }
    })
}

func displayLocationInfo(placemark: CLPlacemark!) {
    if (placemark != nil) {
        //stop updating location to save battery life
        locationLocation.stopUpdatingLocation()
        var tempString : String = ""
        if(placemark.locality != nil){
            tempString = tempString +  placemark.locality! + " "
            print(placemark.locality)
        }
        if(placemark.postalCode != nil){
            tempString = tempString +  placemark.postalCode! + " "
            print(placemark.postalCode)
        }
        if(placemark.administrativeArea != nil){
            tempString = tempString +  placemark.administrativeArea! + " "
            print(placemark.administrativeArea)
        }
        if(placemark.country != nil){
            tempString = tempString +  placemark.country! + " "



        }
        let dictForaddress = placemark.addressDictionary as! NSDictionary


        if let city = dictForaddress["City"] {
            print(city)



        }
        strLocation = tempString
    }
}

// place the function code below in desire location in program.

// [self getCurrentLocation];



-(void)getCurrentLocation
{
    CLGeocoder *geocoder = [[CLGeocoder alloc] init] ;
    [geocoder reverseGeocodeLocation:self->locationManager.location
                   completionHandler:^(NSArray *placemarks, NSError *error) {
                       NSLog(@"reverseGeocodeLocation:completionHandler: Completion Handler called!");

                       if (error){
                           NSLog(@"Geocode failed with error: %@", error);
                           return;

                       }


                       CLPlacemark *placemark = [placemarks objectAtIndex:0];

                       NSLog(@"placemark.ISOcountryCode %@",placemark.ISOcountryCode);
                       NSLog(@"placemark.country %@",placemark.country);
                        NSLog(@"placemark.locality %@",placemark.locality );
                       NSLog(@"placemark.postalCode %@",placemark.postalCode);
                       NSLog(@"placemark.administrativeArea %@",placemark.administrativeArea);
                       NSLog(@"placemark.locality %@",placemark.locality);
                       NSLog(@"placemark.subLocality %@",placemark.subLocality);
                       NSLog(@"placemark.subThoroughfare %@",placemark.subThoroughfare);

                   }];
}

Aquí está mi pequeña clase Swift que me ayuda a obtener información geocodificada inversa sobre la ubicación actual. No se olvide del NSLocationWhenInUseUsageDescriptioncampo de entrada Info.plist.

class CurrentPlacemarkUpdater: NSObject, CLLocationManagerDelegate {

    private let locationManager = CLLocationManager()
    private let geocoder = CLGeocoder()

    private(set) var latestPlacemark: CLPlacemark?
    var onLatestPlacemarkUpdate: (() -> ())?
    var shouldStopOnUpdate: Bool = true

    func start() {
        locationManager.requestWhenInUseAuthorization()
        locationManager.desiredAccuracy = kCLLocationAccuracyKilometer
        locationManager.delegate = self
        locationManager.startUpdatingLocation()
    }

    func stop() {
        locationManager.stopUpdatingLocation()
    }

    fileprivate func updatePlacemark(for location: CLLocation) {
        geocoder.reverseGeocodeLocation(location) { [weak self] placemarks, error in
            if let placemark = placemarks?.first {
                self?.latestPlacemark = placemark
                self?.onLatestPlacemarkUpdate?()
                if self?.shouldStopOnUpdate ?? false {
                    self?.stop()
                }
            }
        }
    }

    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        if let location = locations.last {
            updatePlacemark(for: location)
        }
    }

    func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
        print("CurrentPlacemarkUpdater: \(error)")
    }

}

Lea la documentación de MKReverseGeocoder : Apple proporciona la documentación, las guías y las aplicaciones de muestra por una razón.