bobbymay / Display-Location-Map

Shows a devices location on a map and displays its address using reverse geocoding.

Track Users Location Using CLLocationManager

---

A simple implementation of CLLocationManager. Works in the foreground and background. Displays location on MKMapView. Tapping location on map displays address using reverse geocoding.

Declare instance and set delegate

let locationManager = CLLocationManager()
locationManager.delegate = self

Requests permission to track location.

locationManager.requestAlwaysAuthorization()

Conform to delegate to receive location information

extension ViewController: CLLocationManagerDelegate {

 /// Receives user response to monitor location
 func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
 
  guard status == .authorizedAlways || status == .authorizedWhenInUse else { return }
  locationManager.startUpdatingLocation()
  locationManager.allowsBackgroundLocationUpdates = status == .authorizedAlways ? true : false
 }

 /// Receives location information
 func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
 
  guard let location = locations.last else { return }
  display(location: location)
 }

}

Use reverse geocoding to display address

private func reverseGeocode(location: CLLocation) {

 CLGeocoder().reverseGeocodeLocation(location, completionHandler: { [unowned self] placemark, error in
 
  guard let p = placemark?.first else { self.setAnnotation(subtitle: nil, location: location); return }
  
  // Address Example: 12345 Elm Street, Tampa, FL 33660, United States
  let address = "\(p.subThoroughfare ?? "") \(p.thoroughfare ?? "Unknown"), \(p.locality ?? ""), \(p.administrativeArea ?? "") \(p.postalCode ?? ""), \(p.country ?? "")."
  
  self.setAnnotation(subtitle: address, location: location)
 })
 
}

Set annotation on map

private func setAnnotation(subtitle: String?, location: CLLocation) {

 let annotation = MKPointAnnotation()
 annotation.coordinate = location.coordinate
 annotation.title = "Current Location"
 annotation.subtitle = subtitle
 
 map.addAnnotation(annotation)
}