ios - Find city name and country from latitude and longitude in Swift

Question

I'm working on application in Swift3 and I have letter problem i can't find the answer for it.

How can I know city name and country short names base on latitude and longitude?

import UIKit
import CoreLocation

class ViewController: UIViewController, CLLocationManagerDelegate{
    let locationManager = CLLocationManager()
    var latitude: Double = 0
    var longitude: Double = 0
    override func viewDidLoad() {
        super.viewDidLoad()
        // For use when the app is open & in the background
        locationManager.requestAlwaysAuthorization()
        // For use when the app is open
        //locationManager.requestWhenInUseAuthorization()
        locationManager.delegate = self
        locationManager.startUpdatingLocation()
        if CLLocationManager.locationServicesEnabled() {
            locationManager.delegate = self
            locationManager.desiredAccuracy = kCLLocationAccuracyBest
            locationManager.startUpdatingLocation()
        }
    }
    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        if let location = locations.first {
            print(location.coordinate)
            latitude = location.coordinate.latitude
            longitude = location.coordinate.longitude
        }
    }
    func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
        if (status == CLAuthorizationStatus.denied){
            showLocationDisabledpopUp()
        }
    }
    func showLocationDisabledpopUp() {
        let alertController = UIAlertController(title: "Background Location Access  Disabled", message: "We need your location", preferredStyle: .alert)
        let cancelAction = UIAlertAction(title: "Cancel", style: .cancel, handler: nil)
        alertController.addAction(cancelAction)
        let openAction = UIAlertAction(title: "Open Setting", style: .default) { (action) in
            if let url = URL(string: UIApplicationOpenSettingsURLString){
                UIApplication.shared.open(url, options: [:], completionHandler: nil)
            }
        }
        alertController.addAction(openAction)
        self.present(alertController, animated: true, completion: nil)
    }
}

Answer 1

You can use CLGeocoder reverseGeocodeLocation method to fetch a CLPlacemark and get its country and locality properties info. Note that it is an asynchronous method so you will need to add a completion handler to your method when fetching that info:

import UIKit
import MapKit
import PlaygroundSupport
PlaygroundPage.current.needsIndefiniteExecution = true

extension CLLocation {
    func fetchCityAndCountry(completion: @escaping (_ city: String?, _ country:  String?, _ error: Error?) -> ()) {
        CLGeocoder().reverseGeocodeLocation(self) { completion($0?.first?.locality, $0?.first?.country, $1) }
    }
}

---

Usage

let location = CLLocation(latitude: -22.963451, longitude: -43.198242)
location.fetchCityAndCountry { city, country, error in
    guard let city = city, let country = country, error == nil else { return }
    print(city + ", " + country)  // Rio de Janeiro, Brazil
}

---

edit/update:

iOS 11 or later CLPlacemark has a postalAddress property. You can import Contacts framework and use CNPostalAddressFormatter's string(from:) method to get a localized formatted address. You can also extend CLPlacemark and add some computed properties to better describe some of its properties:

import MapKit
import Contacts

extension CLPlacemark {
    /// street name, eg. Infinite Loop
    var streetName: String? { thoroughfare }
    /// // eg. 1
    var streetNumber: String? { subThoroughfare }
    /// city, eg. Cupertino
    var city: String? { locality }
    /// neighborhood, common name, eg. Mission District
    var neighborhood: String? { subLocality }
    /// state, eg. CA
    var state: String? { administrativeArea }
    /// county, eg. Santa Clara
    var county: String? { subAdministrativeArea }
    /// zip code, eg. 95014
    var zipCode: String? { postalCode }
    /// postal address formatted
    @available(iOS 11.0, *)
    var postalAddressFormatted: String? {
        guard let postalAddress = postalAddress else { return nil }
        return CNPostalAddressFormatter().string(from: postalAddress)
    }
}

---

extension CLLocation {
    func placemark(completion: @escaping (_ placemark: CLPlacemark?, _ error: Error?) -> ()) {
        CLGeocoder().reverseGeocodeLocation(self) { completion($0?.first, $1) }
    }
}

---

Usage:

let location = CLLocation(latitude: 37.331676, longitude: -122.030189)
location.placemark { placemark, error in
    guard let placemark = placemark else { 
        print("Error:", error ?? "nil")
        return
    }
    print(placemark.postalAddressFormatted ?? "")
}

---

This will print

1 Infinite Loop
Cupertino CA 95014
United States

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