public static void InitializePackageManager(string packageFolder,
                                                    string importPackagePath, IMapView mapView, string downloadedPackage)
        {
            // Offline base layer

            // Define listener, definition is in same class above
            var packageManager = new CartoPackageManager("nutiteq.osm", packageFolder);

            packageManager.PackageManagerListener = new PackageListener(packageManager, downloadedPackage);

            // Download new package list only if it is older than 24h
            // Note: this is only needed if pre-made packages are used
            if (packageManager.ServerPackageListAge > 24 * 60 * 60)
            {
                packageManager.StartPackageListDownload();
            }

            // Start manager - mandatory
            packageManager.Start();

            // Import initial package
            if (packageManager.GetLocalPackage("world0_4") == null)
            {
                packageManager.StartPackageImport("world0_4", 1, importPackagePath);
            }

            // Now can add vector map as layer
            // Define styling for vector map
            BinaryData          styleBytes        = AssetUtils.LoadAsset("nutibright-v2a.zip");
            MBVectorTileDecoder vectorTileDecoder = null;

            if (styleBytes != null)
            {
                // Create style set
                var vectorTileStyleSet = new CompiledStyleSet(new ZippedAssetPackage(styleBytes));
                vectorTileDecoder = new MBVectorTileDecoder(vectorTileStyleSet);
            }
            else
            {
                Log.Error("Failed to load style data");
            }

            // Create online base layer (no package download needed then). Use vector style from assets (osmbright.zip)
            // comment in to use online map. Packagemanager stuff is not needed then

            //VectorTileLayer baseLayer = new NutiteqOnlineVectorTileLayer("osmbright.zip");

            var baseLayer = new VectorTileLayer(new PackageManagerTileDataSource(packageManager), vectorTileDecoder);

            mapView.Layers.Add(baseLayer);
        }