# CircleLayer clusters

> **Note (legacy): A newer version of the Maps SDK is available**
> 
> This page uses v9.7.1 of the Mapbox Maps SDK. A newer version of the SDK is available. Learn about the latest version, v11.31.0, in the [Maps SDK documentation](https://docs.mapbox.com/android/maps/guides/).

Your browser doesn't support HTML5 video. Open [link to the video](https://docs.mapbox.com/android/android/assets/medias/maps-example-circle-layer-clustering-activity-b51d674dc3304554c065da58cf3e4e48.mp4).

> **Note**
> 
> This example is a part of the [Mapbox Android Demo app](https://github.com/mapbox/mapbox-android-demo). You can find the values for all referenced resources in the [`res`](https://github.com/mapbox/mapbox-android-demo/tree/master/MapboxAndroidDemo/src/main/res) directory. For example, see [`res/values/activity_strings.xml`](https://github.com/mapbox/mapbox-android-demo/tree/master/MapboxAndroidDemo/src/main/res/values/activity_strings.xml) for `R.string.*` references used in this example. The dependencies can be found [here.](https://github.com/mapbox/mapbox-navigation-android-examples/blob/main/app/build.gradle) The examples use View binding. [See setup documention if necessary.](https://developer.android.com/topic/libraries/view-binding)

Title: `activity_circle_layer_clustering`

[View on GitHub](https://github.com/mapbox/mapbox-android-demo/tree/master/MapboxAndroidDemo/src/main/res/layout/activity_circle_layer_clustering.xml)

```xml
<?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>
```

**Java**

Title: `CircleLayerClusteringActivity.java`

[View on GitHub](https://github.com/mapbox/mapbox-android-demo/tree/master/MapboxAndroidDemo/src/main/java/com/mapbox/mapboxandroiddemo/examples/dds/CircleLayerClusteringActivity.java)

```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);
  }
}
```