title: Xamarin iOS Google Maps SDK - Exception with mapView.AddObserver()
body: <p>I'm trying to get the current position of the device using Google Maps SDK in Xamarin.iOS, I got the following code but I'm getting an exception.</p>
  
  <p>I've imported the Google Maps SDK for iOS in Xamarin</p>
  
  <pre><code>using Google.Maps;
  </code></pre>
  
  <p>This is my code:</p>
  
  <pre><code>MapView gmapView;
  public override void ViewDidLoad ()
  {
      base.ViewDidLoad ();
  
      CameraPosition camera = CameraPosition.FromCamera (latitude: 40.7056308, 
              longitude: -73.9780035, 
              zoom: 13);
      mapView = MapView.FromCamera (new RectangleF(0, 0, View.Frame.Width, View.Frame.Bottom - 50), camera);
      mapView.Settings.CompassButton = true;
      mapView.Settings.MyLocationButton = true;
  
      // Listen to the myLocation property of GMSMapView.
      mapView.AddObserver (this, new NSString ("myLocation"), NSKeyValueObservingOptions.New, IntPtr.Zero);
  
      // More code ...
      // ...
  
      // Ask for My Location data after the map has already been added to the UI.
      InvokeOnMainThread (()=&gt; mapView.MyLocationEnabled = true);
  }
  </code></pre>
  
  <p>Then I define the method that should be called when the position of the user changes:</p>
  
  <pre><code>public override void ObserveValue (NSString keyPath, NSObject ofObject, NSDictionary change, IntPtr context)
  {
      if (!firstLocationUpdate) {
          // If the first location update has not yet been recieved, then jump to that
          // location.
          firstLocationUpdate = true; 
          var location = change.ObjectForKey (NSValue.ChangeNewKey) as CLLocation;
          mapView.Camera = CameraPosition.FromCamera (location.Coordinate, 14);
      }
  }
  </code></pre>
  
  <p>But I'm getting the following exception and have been stuck with this for a while with no luck :/</p>
  
  <pre><code>MonoTouch.Foundation.MonoTouchException: Objective-C exception thrown.  Name: NSInternalInconsistencyException Reason: &lt;MapViewController: 0x1b6648c0&gt;: An -   observeValueForKeyPath:ofObject:change:context: message was received but not handled.
  </code></pre>