pinch and zoom on apple mapkit swift - ios

Question

I have been able to implement MapKit into my app, but it currently looks the map in one static position.
I have been struggling to add the pinch and zoom functionality as well as the ability to allow users to explore other regions on the map.
Here is what my current code looks like:
import UIKit
import MapKit
import CoreLocation
class HotPlacesViewController: UIViewController, CLLocationManagerDelegate, MKMapViewDelegate {
#IBOutlet weak var mapView: MKMapView!
var locationManager = CLLocationManager()
let newPin = MKPointAnnotation()
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
// Setup the location services delegate in this class.
locationManager.delegate = self
// This little method requests the users permission for location services whilst in this view controller.
if CLLocationManager.authorizationStatus() == .notDetermined {
self.locationManager.requestAlwaysAuthorization()
let alert = UIAlertController(title: "You can change this option in the Settings App", message: "So keep calm your selection is not permanent. 🙂",
preferredStyle: .alert)
alert.addAction(UIAlertAction(title: "OK", style: .default, handler: nil))
self.present(alert, animated: true, completion: nil)
}
locationManager.distanceFilter = kCLDistanceFilterNone
locationManager.desiredAccuracy = kCLLocationAccuracyBest
locationManager.startUpdatingLocation()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
}
// Drops the pin on the users current location.
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
mapView.removeAnnotation(newPin)
let location = locations.last! as CLLocation
let center = CLLocationCoordinate2D(latitude: location.coordinate.latitude, longitude: location.coordinate.longitude)
let region = MKCoordinateRegion(center: center, span: MKCoordinateSpan(latitudeDelta: 0.01, longitudeDelta: 0.01))
// Set the region on the map.
mapView.setRegion(region, animated: true)
newPin.coordinate = location.coordinate
mapView.addAnnotation(newPin)
}
}

Answer 1

I think that you problem is related to this method func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]), because over and over again when the position is updated you are adjusting the region in the map that is why you see only the region where the position is updated and can't move any other region in the map, you must make a flag for first time and adjust the region only once or don't adjust the region at all
EDITED
import UIKit
import MapKit
import CoreLocation
class HotPlacesViewController: UIViewController, CLLocationManagerDelegate, MKMapViewDelegate {
#IBOutlet weak var mapView: MKMapView!
var isFirstTime = true
var locationManager = CLLocationManager()
let newPin = MKPointAnnotation()
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
// Setup the location services delegate in this class.
locationManager.delegate = self
// This little method requests the users permission for location services whilst in this view controller.
if CLLocationManager.authorizationStatus() == .notDetermined {
self.locationManager.requestAlwaysAuthorization()
let alert = UIAlertController(title: "You can change this option in the Settings App", message: "So keep calm your selection is not permanent. 🙂",
preferredStyle: .alert)
alert.addAction(UIAlertAction(title: "OK", style: .default, handler: nil))
self.present(alert, animated: true, completion: nil)
}
locationManager.distanceFilter = kCLDistanceFilterNone
locationManager.desiredAccuracy = kCLLocationAccuracyBest
locationManager.startUpdatingLocation()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
}
// Drops the pin on the users current location.
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
mapView.removeAnnotation(newPin)
let location = locations.last! as CLLocation
let center = CLLocationCoordinate2D(latitude: location.coordinate.latitude, longitude: location.coordinate.longitude)
if(self.isFirstTime){
let region = MKCoordinateRegion(center: center, span: MKCoordinateSpan(latitudeDelta: 0.01, longitudeDelta: 0.01))
// Set the region on the map.
mapView.setRegion(region, animated: true)
self.isFirstTime = false
}
newPin.coordinate = location.coordinate
mapView.addAnnotation(newPin)
}
}
Hope this helps, and let me know if I misunderstood your question

Answer 2

let region = MKCoordinateRegion(center: center, span: MKCoordinateSpan(latitudeDelta: 0.01, longitudeDelta: 0.01))
mapView.setRegion(region, animated: true)
Set span for zoom in MapKit