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CircleLayer clusters

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This page uses v9.7.1 of the Mapbox Maps SDK. A newer version of the SDK is available. Learn about the latest version, v11.8.1, in the Maps SDK documentation.
Note

This example is a part of the Mapbox Android Demo app. You can find the values for all referenced resources in the res directory. For example, see res/values/activity_strings.xml for R.string.* references used in this example. The dependencies can be found here.The examples use View binding.See setup documention if necessary.

activity_circle_layer_clustering
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.mapbox.mapboxandroiddemo.examples.dds.CircleLayerClusteringActivity">

<com.mapbox.mapboxsdk.maps.MapView
android:id="@+id/mapView"
android:layout_width="match_parent"
android:layout_height="match_parent"/>

</FrameLayout>
CircleLayerClusteringActivity.java
package com.mapbox.mapboxandroiddemo.examples.dds;

import android.graphics.Color;
import android.os.Bundle;
import android.widget.Toast;

import com.mapbox.mapboxandroiddemo.R;
import com.mapbox.mapboxsdk.Mapbox;
import com.mapbox.mapboxsdk.camera.CameraUpdateFactory;
import com.mapbox.mapboxsdk.geometry.LatLng;
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.CircleLayer;
import com.mapbox.mapboxsdk.style.layers.SymbolLayer;
import com.mapbox.mapboxsdk.style.layers.TransitionOptions;
import com.mapbox.mapboxsdk.style.sources.GeoJsonOptions;
import com.mapbox.mapboxsdk.style.sources.GeoJsonSource;
import com.mapbox.mapboxsdk.utils.BitmapUtils;

import java.net.URI;
import java.net.URISyntaxException;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.content.ContextCompat;
import timber.log.Timber;

import static com.mapbox.mapboxsdk.style.expressions.Expression.all;
import static com.mapbox.mapboxsdk.style.expressions.Expression.division;
import static com.mapbox.mapboxsdk.style.expressions.Expression.exponential;
import static com.mapbox.mapboxsdk.style.expressions.Expression.get;
import static com.mapbox.mapboxsdk.style.expressions.Expression.gte;
import static com.mapbox.mapboxsdk.style.expressions.Expression.has;
import static com.mapbox.mapboxsdk.style.expressions.Expression.interpolate;
import static com.mapbox.mapboxsdk.style.expressions.Expression.literal;
import static com.mapbox.mapboxsdk.style.expressions.Expression.lt;
import static com.mapbox.mapboxsdk.style.expressions.Expression.rgb;
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.circleColor;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.circleRadius;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.iconColor;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.iconImage;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.iconSize;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.textAllowOverlap;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.textColor;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.textField;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.textIgnorePlacement;
import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.textSize;

/**
* Use GeoJSON and circle layers to visualize point data as circle clusters.
*/
public class CircleLayerClusteringActivity extends AppCompatActivity {

private MapView mapView;
private MapboxMap mapboxMap;

@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 access token is configured.
setContentView(R.layout.activity_circle_layer_clustering);

mapView = findViewById(R.id.mapView);

mapView.onCreate(savedInstanceState);
mapView.getMapAsync(new OnMapReadyCallback() {
@Override
public void onMapReady(@NonNull MapboxMap map) {

mapboxMap = map;

map.setStyle(Style.LIGHT, new Style.OnStyleLoaded() {
@Override
public void onStyleLoaded(@NonNull Style style) {

// Disable any type of fading transition when icons collide on the map. This enhances the visual
// look of the data clustering together and breaking apart.
style.setTransition(new TransitionOptions(0, 0, false));

mapboxMap.animateCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(
12.099, -79.045), 3));

addClusteredGeoJsonSource(style);
style.addImage(
"cross-icon-id",
BitmapUtils.getBitmapFromDrawable(getResources().getDrawable(R.drawable.ic_cross)),
true
);

Toast.makeText(CircleLayerClusteringActivity.this, R.string.zoom_map_in_and_out_instruction,
Toast.LENGTH_SHORT).show();
}
});
}
});
}

private void addClusteredGeoJsonSource(@NonNull Style loadedMapStyle) {

// Add a new source from the GeoJSON data and set the 'cluster' option to true.
try {
loadedMapStyle.addSource(
// Point to GeoJSON data. This example visualizes all M1.0+ earthquakes from
// 12/22/15 to 1/21/16 as logged by USGS' Earthquake hazards program.
new GeoJsonSource("earthquakes",
new URI("https://www.mapbox.com/mapbox-gl-js/assets/earthquakes.geojson"),
new GeoJsonOptions()
.withCluster(true)
.withClusterMaxZoom(14)
.withClusterRadius(50)
)
);
} catch (URISyntaxException uriSyntaxException) {
Timber.e("Check the URL %s", uriSyntaxException.getMessage());
}

//Creating a marker layer for single data points
SymbolLayer unclustered = new SymbolLayer("unclustered-points", "earthquakes");

unclustered.setProperties(
iconImage("cross-icon-id"),
iconSize(
division(
get("mag"), literal(4.0f)
)
),
iconColor(
interpolate(exponential(1), get("mag"),
stop(2.0, rgb(0, 255, 0)),
stop(4.5, rgb(0, 0, 255)),
stop(7.0, rgb(255, 0, 0))
)
)
);
unclustered.setFilter(has("mag"));
loadedMapStyle.addLayer(unclustered);

// Use the earthquakes GeoJSON source to create three layers: One layer for each cluster category.
// Each point range gets a different fill color.
int[][] layers = new int[][] {
new int[] {150, ContextCompat.getColor(this, R.color.mapboxRed)},
new int[] {20, ContextCompat.getColor(this, R.color.mapboxGreen)},
new int[] {0, ContextCompat.getColor(this, R.color.mapbox_blue)}
};

for (int i = 0; i < layers.length; i++) {
//Add clusters' circles
CircleLayer circles = new CircleLayer("cluster-" + i, "earthquakes");
circles.setProperties(
circleColor(layers[i][1]),
circleRadius(18f)
);

Expression pointCount = toNumber(get("point_count"));

// Add a filter to the cluster layer that hides the circles based on "point_count"
circles.setFilter(
i == 0
? all(has("point_count"),
gte(pointCount, literal(layers[i][0]))
) : all(has("point_count"),
gte(pointCount, literal(layers[i][0])),
lt(pointCount, literal(layers[i - 1][0]))
)
);
loadedMapStyle.addLayer(circles);
}

//Add the count labels
SymbolLayer count = new SymbolLayer("count", "earthquakes");
count.setProperties(
textField(Expression.toString(get("point_count"))),
textSize(12f),
textColor(Color.WHITE),
textIgnorePlacement(true),
textAllowOverlap(true)
);
loadedMapStyle.addLayer(count);
}

@Override
public void onStart() {
super.onStart();
mapView.onStart();
}

@Override
public void onResume() {
super.onResume();
mapView.onResume();
}

@Override
public void onPause() {
super.onPause();
mapView.onPause();
}

@Override
public 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);
}
}