title: Use .GetMapAsync instead .getMap method with Google Play Services (Xamarin)
body: <p>An old code works perfectly in this way:</p>
  
  <pre><code>LatLng location = new LatLng (myClass.myLocation.Latitude, myClass.myLocation.Longitude);
  CameraPosition.Builder builder = CameraPosition.InvokeBuilder ();
  builder.Target (location);
  builder.Zoom (18);
  CameraPosition cameraPosition = builder.Build ();
  MapsInitializer.Initialize (this);
  CameraUpdate cameraUpdate = CameraUpdateFactory.NewCameraPosition (cameraPosition);
  MapFragment googleMap = FragmentManager.FindFragmentById&lt;MapFragment&gt; (Resource.Id.map);
  theMap = googleMap.Map;
  if (theMap != null) {
      theMap.MapType = GoogleMap.MapTypeNormal;
      theMap.MoveCamera (cameraUpdate);
  }
  </code></pre>
  
  <p>but now that the <code>.Map</code> is obsolete and deprecated, I must to use <code>.GetMapAsync</code> in some way:</p>
  
  <pre><code>theMap = googleMap.GetMapAsync (IOnMapReadyCallback);
  </code></pre>
  
  <p>But I don't understand how.</p>
  
  <p>There is somebody that can help me?</p>