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Style lines using an identity property function

A newer version of the Maps SDK is available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 A newer version of the SDK is available.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, v11.7.0, 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_style_line
<?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.StyleLineIdentityPropertyActivity">

<com.mapbox.mapboxsdk.maps.MapView
android:id="@+id/mapView"
android:layout_width="match_parent"
android:layout_height="match_parent"
mapbox:mapbox_cameraTargetLat="37.82882682974591"
mapbox:mapbox_cameraTargetLng="-122.48383155304096"
mapbox:mapbox_cameraZoom="15.3"/>

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

import android.os.Bundle;

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.layers.LineLayer;
import com.mapbox.mapboxsdk.style.layers.Property;
import com.mapbox.mapboxsdk.style.layers.PropertyFactory;
import com.mapbox.mapboxsdk.style.sources.GeoJsonSource;

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

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
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.rgb;
import static com.mapbox.mapboxsdk.style.expressions.Expression.stop;

/**
* Use data-driven styling to set a line's color based on imported GeoJSON.
*/
public class StyleLineIdentityPropertyActivity extends AppCompatActivity {

private MapView mapView;

@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_style_line);

mapView = findViewById(R.id.mapView);
mapView.onCreate(savedInstanceState);
mapView.getMapAsync(new OnMapReadyCallback() {
@Override
public void onMapReady(@NonNull final MapboxMap mapboxMap) {

mapboxMap.setStyle(Style.MAPBOX_STREETS, new Style.OnStyleLoaded() {
@Override
public void onStyleLoaded(@NonNull Style style) {
try {
// Retrieve GeoJSON from local file and add it to the map
style.addSource(new GeoJsonSource("lines",
new URI("asset://golden_gate_lines.geojson")));
} catch (URISyntaxException exception) {
Timber.d(exception);
}

// Create a LineLayer. Use lineColor and stops to draw red and blue lines on the map
style.addLayer(new LineLayer("finalLines", "lines").withProperties(
PropertyFactory.lineColor(
match(get("color"), rgb(0, 0, 0),
stop("red", rgb(247, 69, 93)),
stop("blue", rgb(51, 201, 235)))),
PropertyFactory.visibility(Property.VISIBLE),
PropertyFactory.lineWidth(3f)
));
}
});
}
});
}

@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);
}
}