public void OnMapReady(MapboxMap mapboxMap)
        {
            this.mapboxMap     = mapboxMap;
            navigationMapRoute = new NavigationMapRoute(null, mapView, mapboxMap, "admin-3-4-boundaries-bg");
            Gson gson = new GsonBuilder().RegisterTypeAdapterFactory(DirectionsAdapterFactory.Create()).Create();
            var  json = loadJsonFromAsset(DIRECTIONS_RESPONSE);
            DirectionsResponse response = (DirectionsResponse)gson.FromJson(json, Class.FromType(typeof(DirectionsResponse)));

            navigationMapRoute.AddRoute(response.Routes()[0]);
            mapboxMap.SetOnMapLongClickListener(this);
            navigationMapRoute.SetOnRouteSelectionChangeListener(this);
        }