Implementing own TileServerProvider

Question

I am using HERE Maps SDK Lite Edition Version 4.7.3.0, which gives the possibility to ad a RasterLayer with an own TileServerProvider implementation (see documentation).

I edited the given example by exchanging the SimpleTileServerProvider with my own implementation.

      RasterLayer myCustomLayer = new RasterLayer("CUSTOM_LAYER",
          17,
          1001,
          new TileServerProvider() {
             @NonNull
             @NotNull
             @Override
             public String provideURL(long x, long y, long zoom) {
                return "myURI";
             }
          });

When adding this RasterLayer to my MapView, provideURI is called, but only 0 values are passed to the parameters of provideURI. What is getting wrong here?

Answer 1

In my production code I did not enter 17 for parameter maxZoomLevel directly, but took this value from a function. But this function did return 0 instead.

Answer 2

I am glad to help you. To load custom Raster layers, the format of the URL should be as follows:

https://YourRasterTileService.com/zoom/xTile/yTile.png.

I am successfully able to load the Custom Raster with the example you have mentioned in the Here documentation link.

  String myCustomRasterLayerName = "my_custom_raster_layer";
  long maxZoom = 19;
  long drawOrder = 1000;
  TileServerProvider staticTileServerProvider = new SimpleTileServerProvider("https://a.tile.openstreetmap.org/{z}/{x}/{y}.png");

  RasterLayer rasterLayer = new RasterLayer(
          myCustomRasterLayerName,
          maxZoom,
          drawOrder,
          staticTileServerProvider);

  mapSceneConfig = new MapSceneConfig();
  mapSceneConfig.rasterLayers.add(rasterLayer);
  mapSceneConfig.customMapLayers.put(myCustomRasterLayerName, LayerState.ENABLED);

  mapView.getMapScene().loadScene(MapStyle.EMPTY, mapSceneConfig, new MapScene.LoadSceneCallback() {
      @Override
      public void onLoadScene(@Nullable MapScene.ErrorCode errorCode) {
          if (errorCode != null) {
              Log.d(TAG, "onLoadScene failed: " + errorCode.toString());
          }
      }
  });

If you would like me to investigate further specific to your code implementation of TileServerProvider, please share the code implementation integrated in one of the sample app downloadable from the below link.

https://github.com/heremaps/here-sdk-examples/tree/master/examples/latest/lite/android/MapOverlaysLite