title: Add resizable circle radius on GoogleMaps API for iOS
body: <p>I am trying to make a circle-like-radius area that user can resize and I can get the number of radius of my current location. </p>
  
  <p>================</p>
  
  <p>tl;dr <strong>Edited</strong></p>
  
  <p><strong><em>I want to make <a href="http://jsfiddle.net/bmf5p500/2/" rel="nofollow noreferrer">this</a> as an iOS app with swift.</em></strong></p>
  
  <p>=================</p>
  
  <p>Right now, I already created map that listening to current location. Using <code>CLLocationManager</code>, I am observing its update location and the map will show my location.</p>
  
  <pre><code>import UIKit
  import GoogleMaps
  
  class ViewController: UIViewController, CLLocationManagerDelegate {
      @IBOutlet var mapView: GMSMapView!
  
      // Current Location Components
      var locationManager = CLLocationManager()
      var didFindMyLocation = false
  
      override func viewDidLoad() {
          super.viewDidLoad()
  
          // Current Location Delegate
          locationManager.delegate = self
          locationManager.requestWhenInUseAuthorization()
  
          // Observer for update location (Moving)
          mapView.addObserver(self, forKeyPath: "myLocation", options: NSKeyValueObservingOptions.New, context: nil)
      }
  
      // Core Location Location Manager Delegate
      func locationManager(manager: CLLocationManager, didChangeAuthorizationStatus status: CLAuthorizationStatus) {
          if status == CLAuthorizationStatus.AuthorizedWhenInUse {
              mapView.myLocationEnabled = true
          }
      }
  
      override func observeValueForKeyPath(keyPath: String?, ofObject object: AnyObject?, change: [String : AnyObject]?, context: UnsafeMutablePointer&lt;Void&gt;) {
          if !didFindMyLocation {
              let myLocation: CLLocation = change![NSKeyValueChangeNewKey] as! CLLocation
              mapView.camera = GMSCameraPosition.cameraWithTarget(myLocation.coordinate, zoom: 18.0)
              mapView.settings.myLocationButton = true
  
              didFindMyLocation = true
          }
      }
  </code></pre>
  
  <p>Right now I want to make a circle that resizable. Someone already created that in android <a href="https://stackoverflow.com/questions/18960164/android-draw-resizable-circle-on-google-map">here</a>. The circle/radius could be shrink or expand by gesture, and I can get the radius of that circle from its center like this <a href="https://stackoverflow.com/questions/32722122/get-radius-while-resizing-circle?rq=1">question</a>. This is what I want for my app.</p>
  
  <p>So, what should I use for this radius-circle-resizable? I am really appreciate every answers and ideas. Thank you!</p>