Spatialite layer

AdvancedLayers includes already pre-compiled version of Spatialite native library with dependencies (sqlite and proj.4).

Following code shows usage of the layer, with several tables in one view:

        // minimum zoom to show data
        int minZoom = 10;

        // open database connection, query metadata
        try {
            spatialLite = new SpatialLiteDbHelper(dbPath);
        } catch (IOException e) {
            Log.error(e.getLocalizedMessage());
            Toast.makeText(this, "ERROR "+e.getLocalizedMessage(), Toast.LENGTH_LONG).show();
            return;
        }
        dbMetaData = spatialLite.qrySpatialLayerMetadata();

        ArrayList<String> tables = new ArrayList<String>();

        for (String layerKey : dbMetaData.keySet()) {
            SpatialLiteDbHelper.DbLayer layer = dbMetaData.get(layerKey);
            Log.debug("layer: " + layer.table + " " + layer.type + " geom:"
                    + layer.geomColumn+ " SRID: "+layer.srid);
        }

        // define styles for all 3 object types: point, line and polygon
        StyleSet<PointStyle> pointStyleSet = new StyleSet<PointStyle>();
        PointStyle pointStyle = PointStyle.builder().setSize(0.05f).setColor(Color.BLACK).build();
        pointStyleSet.setZoomStyle(minZoom, pointStyle);

        StyleSet<LineStyle> lineStyleSet = new StyleSet<LineStyle>();
        lineStyleSet.setZoomStyle(minZoom, LineStyle.builder().setWidth(0.1f).setColor(Color.GREEN).build());

        PolygonStyle polygonStyle = PolygonStyle.builder().setColor(Color.BLUE).build();
        StyleSet<PolygonStyle> polygonStyleSet = new StyleSet<PolygonStyle>(null);
        polygonStyleSet.setZoomStyle(minZoom, polygonStyle);

        // define datasource for Spatialite. Here you define also labels and styles for elements.
        // replace TABLE_NAME and GEOMETRY_COLUMN_NAME for your table name and column name
        SpatialiteDataSource dataSource = new SpatialiteDataSource(new EPSG3857(), spatialLite, "TABLE_NAME", "GEOMETRY_COLUMN_NAME", null, null) {
            @Override
            protected Label createLabel(Map<String, String> userData) {
                  // create popup label for object based on attribute values - here just add all table fields
                  StringBuffer labelTxt = new StringBuffer();
                  for(Map.Entry<String, String> entry : userData.entrySet()){
                      labelTxt.append(entry.getKey() + ": " + entry.getValue() + "\n");
                  }
                  return new DefaultLabel("Data:", labelTxt.toString(), labelStyle);

            }

            // to make styles depending on object attributes use userData (see createLabel)
            @Override
            protected StyleSet<PointStyle> createPointStyleSet(Map<String, String> userData, int zoom) {
                return pointStyleSet;
            }

            @Override
            protected StyleSet<LineStyle> createLineStyleSet(Map<String, String> userData, int zoom) {
                return lineStyleSet;
            }

            @Override
            protected StyleSet<PolygonStyle> createPolygonStyleSet(Map<String, String> userData, int zoom) {
                return polygonStyleSet;
            }
        };

        // do not load more than 1000 objects - avoid memory overflow. you can load more points, less polygons
        dataSource.setMaxElements(1000);

        // define 2 pixel accuracy (based on screen width) for automatic polygon/line simplification
        DisplayMetrics metrics = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getMetrics(metrics);
        dataSource.setAutoSimplify(2, metrics.widthPixels);

        // create and add layer to map
        GeometryLayer spatialiteLayer = new GeometryLayer(dataSource);
        mapView.getLayers().addLayer(spatialiteLayer);

        // finally zoom mapView to map data extents
        Envelope extent = spatialiteLayer.getDataExtent();
        mapView.setBoundingBox(new Bounds(extent.minX, extent.maxY, extent.maxX, extent.minY), false);