Examples
Getting started (3)Create a simple map viewDynamically build a map viewSupport map fragmentDynamic styling (30)HillshadingAdd a vector tile sourceAdd a new layer below labelsAnimate marker positionAdjust a layer's opacityShow time lapseAnimated image source (GIF)Icon update based on API responseChange a layer's colorChange a map's languageColor dependent on zoom levelClick to add photoIndoor MapMarker following routeStyle with missing iconSymbol layer iconsPicture in picturePulsing layer opacityAdd a WMS sourceText anchor positionButton interaction stylingOpacity fadeShow and hide layersSymbolLayer iconsAdjust text labelsMultiple text formatsTransparent render surfaceUse an image sourceAnimated icon movementVariable label placementExtrusions (5)Adjust light location and colorDisplay 3D building height based on vector dataExtrude polygons for 3D indoor mappingRotate and tilt with 3D buildingsUse GeoJSON data to set extrusion heightCamera (5)Animate the map cameraFit camera in bounding boxRestrict map panningRotating cameraZoom to show a cluster's leavesData visualization (33)Baseball spray chartDisplay water depthBiometric fingerprintCalendar integrationCircle icon toggleCircleLayer clustersCircle radiusCircle to icon transitionCreate a line layerCreate hotspots from pointsData time lapseShow heatmap dataDraw a GeoJSON lineDraw a polygon with holesDraw a polygonDraw multiple geometriesJoin local JSON data with vector tile geometriesLine gradientLine behind moving iconMultiple expressionsIcon setting based on Feature propertyOutlined polygon holeSatellite land selectShared preferencesSpinning iconStyle circles categoricallyStyle lines using an identity property functionToggle collision detectionSymbolLayer clusteringSymbol layer info windowZoom-based icon switchUpdate a choropleth layer by zoom levelStyling heatmapsOffline (3)Cache managementA simple offline mapOffline managerQuerying the map (3)Building outlineQuery a map featureSelect a buildingMap style (4)Style attributionLocal style or custom raster styleDefault stylesMapbox Studio styleUser interaction (12)Click on single layerFeature countDrawing search areaHighlighted lineSymbol layer icon size changeInset mapLocation pickerBackground fogRecyclerView DirectionsSearch again in an areaSnaking directionsRecyclerView interactionImage generation (2)Snapshot NotificationShare snapshot imageDevice location (7)Track device locationBasic pulsing locationLocation camera optionsCustom pulsing locationCustomized location iconShow a user's location on a map fragmentShow a user's location

Join local JSON data with vector tile geometries

activity_choropleth_json_vector_mix
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:mapbox="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.mapbox.mapboxandroiddemo.examples.dds.ChoroplethJsonVectorMixActivity">
<com.mapbox.mapboxsdk.maps.MapView
android:id="@+id/mapView"
android:layout_width="match_parent"
android:layout_height="match_parent"
mapbox:mapbox_cameraTargetLat="38.00312"
mapbox:mapbox_cameraTargetLng="-98.398423"
mapbox:mapbox_cameraZoom="1"/>
</FrameLayout>
ChoroplethJsonVectorMixActivity.java
package com.mapbox.mapboxandroiddemo.examples.dds;
import android.os.AsyncTask;
import android.os.Bundle;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import com.mapbox.mapboxandroiddemo.R;
import com.mapbox.mapboxsdk.Mapbox;
import com.mapbox.mapboxsdk.maps.MapView;
import com.mapbox.mapboxsdk.maps.MapboxMap;
import com.mapbox.mapboxsdk.maps.OnMapReadyCallback;
import com.mapbox.mapboxsdk.maps.Style;
import com.mapbox.mapboxsdk.style.expressions.Expression;
import com.mapbox.mapboxsdk.style.layers.FillLayer;
import com.mapbox.mapboxsdk.style.sources.VectorSource;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.InputStream;
import java.lang.ref.WeakReference;
import java.util.Scanner;
import timber.log.Timber;
import static com.mapbox.mapboxsdk.style.expressions.Expression.get;
import static com.mapbox.mapboxsdk.style.expressions.Expression.match;
import static com.mapbox.mapboxsdk.style.expressions.Expression.rgba;
import static com.mapbox.mapboxsdk.style.expressions.Expression.stop;
import static com.mapbox.mapboxsdk.style.expressions.Expression.toNumber;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.fillColor;
/**
* Style a choropleth map by merging local JSON data with vector tile geometries
*/
public class ChoroplethJsonVectorMixActivity extends AppCompatActivity implements OnMapReadyCallback {
private static final String STATE_UNEMPLOYMENT_INFO_JSON_FILE = "state_unemployment_info.json";
private static final String VECTOR_SOURCE_NAME = "states";
private static final String DATA_MATCH_PROP = "STATE_ID";
private static final String DATA_STYLE_UNEMPLOYMENT_PROP = "unemployment";
private MapView mapView;
private MapboxMap mapboxMap;
private JSONArray statesArray;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Mapbox access token is configured here. This needs to be called either in your application
// object or in the same activity which contains the mapview.
Mapbox.getInstance(this, getString(R.string.access_token));
// This contains the MapView in XML and needs to be called after the account manager
setContentView(R.layout.activity_choropleth_json_vector_mix);
mapView = findViewById(R.id.mapView);
mapView.onCreate(savedInstanceState);
mapView.getMapAsync(this);
}
@Override
public void onMapReady(@NonNull final MapboxMap map) {
this.mapboxMap = map;
map.setStyle(Style.LIGHT, new Style.OnStyleLoaded() {
@Override
public void onStyleLoaded(@NonNull Style style) {
// Add Mapbox-hosted vector source for state polygons
style.addSource(new VectorSource(VECTOR_SOURCE_NAME, "mapbox://mapbox.us_census_states_2015"));
new LoadJson(ChoroplethJsonVectorMixActivity.this).execute();
}
});
}
/**
* Create layer from the vector tile source with data-driven style
*
* @param stops the array of stops to use in the FillLayer
*/
private void addDataToMap(@NonNull Expression.Stop[] stops) {
FillLayer statesJoinLayer = new FillLayer("states-join", VECTOR_SOURCE_NAME);
statesJoinLayer.setSourceLayer(VECTOR_SOURCE_NAME);
statesJoinLayer.withProperties(
fillColor(match(toNumber(get(DATA_MATCH_PROP)),
rgba(0, 0, 0, 1), stops))
);
// Add layer to map below the "waterway-label" layer
if (mapboxMap != null) {
mapboxMap.getStyle(style -> style.addLayerAbove(statesJoinLayer, "waterway-label"));
}
}
private static class LoadJson extends AsyncTask<Void, Void, Expression.Stop[]> {
private WeakReference<ChoroplethJsonVectorMixActivity> weakReference;
private static final String TAG = "ChJSonVectorMix";
LoadJson(ChoroplethJsonVectorMixActivity activity) {
this.weakReference = new WeakReference<>(activity);
}
@Override
protected Expression.Stop[] doInBackground(Void... voids) {
try {
ChoroplethJsonVectorMixActivity activity = weakReference.get();
if (activity != null) {
InputStream inputStream = activity.getAssets().open(STATE_UNEMPLOYMENT_INFO_JSON_FILE);
activity.statesArray = new JSONArray(convertStreamToString(inputStream));
// Create stops array
Expression.Stop[] stops = new Expression.Stop[activity.statesArray.length()];
for (int x = 0; x < activity.statesArray.length(); x++) {
try {
// Generate green color value for each state/stop
JSONObject singleState = activity.statesArray.getJSONObject(x);
double green = singleState.getDouble(DATA_STYLE_UNEMPLOYMENT_PROP) / 14 * 255;
// Add new stop to array of stops
stops[x] = stop(
Double.parseDouble(singleState.getString(DATA_MATCH_PROP)),
rgba(0, green, 0, 1)
);
} catch (JSONException exception) {
throw new RuntimeException(exception);
}
}
return stops;
}
} catch (Exception exception) {
Timber.d("Exception Loading GeoJSON: %s", exception.toString());
}
return null;
}
static String convertStreamToString(InputStream is) {
Scanner scanner = new Scanner(is).useDelimiter("\\A");
return scanner.hasNext() ? scanner.next() : "";
}
@Override
protected void onPostExecute(@Nullable Expression.Stop[] stopsArray) {
super.onPostExecute(stopsArray);
ChoroplethJsonVectorMixActivity activity = weakReference.get();
if (activity != null && stopsArray != null) {
activity.addDataToMap(stopsArray);
}
}
}
@Override
protected void onStart() {
super.onStart();
mapView.onStart();
}
@Override
public void onResume() {
super.onResume();
mapView.onResume();
}
@Override
public void onPause() {
super.onPause();
mapView.onPause();
}
@Override
protected void onStop() {
super.onStop();
mapView.onStop();
}
@Override
public void onLowMemory() {
super.onLowMemory();
mapView.onLowMemory();
}
@Override
protected void onDestroy() {
super.onDestroy();
mapView.onDestroy();
}
@Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
mapView.onSaveInstanceState(outState);
}
}
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