In Apple’s iOS Reminders app, you can set a location area at which you would be reminded of your reminder. When you set the location area, you are allowed to draw a circle that covers the area of the location you want to be reminded at. How would I duplicate this feature. I particularly would like to know how to allow the user to resize the circle on a map view by dragging his finger on the edge of the circle. I have already figured out how to create the circle.
Here is my code so far:
import UIKit
import MapKit
class ViewController: UIViewController {
// MARK: - Outlets
@IBOutlet weak var mapView: MKMapView!
// MARK: - Variables and Constants
let regionRadius: CLLocationDistance = 1000
let circularRegionRadius: CLLocationDistance = 500
let locationManager = CLLocationManager()
// MARK: - View
override func viewDidLoad() {
super.viewDidLoad()
mapView.delegate = self
locationManager.delegate = self
locationManager.requestAlwaysAuthorization()
locationManager.requestWhenInUseAuthorization()
locationManager.desiredAccuracy = kCLLocationAccuracyBest
locationManager.startUpdatingLocation()
centerMapOnLocation(location: locationManager.location!)
}
// MARK: - Actions
@IBAction func addRegion(_ sender: UILongPressGestureRecognizer) {
print("addRegion(_:)")
let longPress = sender
let touchLocation = longPress.location(in: mapView)
let coordinates = mapView.convert(touchLocation, toCoordinateFrom: mapView)
let region = CLCircularRegion(center: coordinates, radius: circularRegionRadius, identifier: "geofence")
mapView.removeOverlays(mapView.overlays)
locationManager.startMonitoring(for: region)
let circle = MKCircle(center: coordinates, radius: region.radius)
mapView.add(circle)
}
// MARK: - Helper Functions
func centerMapOnLocation(location: CLLocation) {
let coordinateRegion = MKCoordinateRegionMakeWithDistance(location.coordinate,
regionRadius, regionRadius)
mapView.setRegion(coordinateRegion, animated: true)
}
// MARK: - Memory Warning
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
extension ViewController: MKMapViewDelegate {
func mapView(_ mapView: MKMapView, rendererFor overlay: MKOverlay) -> MKOverlayRenderer {
print("mapView(_:rendererFor:_:)")
guard let circelOverLay = overlay as? MKCircle else {return MKOverlayRenderer()}
let circleRenderer = MKCircleRenderer(circle: circelOverLay)
circleRenderer.strokeColor = .blue
circleRenderer.fillColor = .blue
circleRenderer.alpha = 0.2
return circleRenderer
}
}
extension ViewController: CLLocationManagerDelegate {
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
print("locationManager(_:didUpdateLocations:)")
locationManager.stopUpdatingLocation()
mapView.showsUserLocation = true
}
}