diff --git a/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/expressions/Expression.java b/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/expressions/Expression.java
index 1aa0ce90932..271ad64f658 100644
--- a/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/expressions/Expression.java
+++ b/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/expressions/Expression.java
@@ -1143,6 +1143,32 @@ public static Expression heatmapDensity() {
return new Expression("heatmap-density");
}
+ /**
+ * Gets the progress along a gradient line. Can only be used in the line-gradient property.
+ * <p>
+ * Example usage:
+ * </p>
+ * <pre>
+ * {@code
+ * LineLayer layer = new LineLayer("layer-id", "source-id");
+ * layer.setProperties(
+ * lineGradient(interpolate(
+ * linear(), lineProgress(),
+ * stop(0f, rgb(0, 0, 255)),
+ * stop(0.5f, rgb(0, 255, 0)),
+ * stop(1f, rgb(255, 0, 0)))
+ * )
+ * )
+ * }
+ * </pre>
+ *
+ * @return expression
+ * @see <a href="https://www.mapbox.com/mapbox-gl-js/style-spec/#expressions-line-progress">Style specification</a>
+ */
+ public static Expression lineProgress() {
+ return new Expression("line-progress");
+ }
+
/**
* Retrieves an item from an array.
*
diff --git a/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/sources/GeoJsonOptions.java b/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/sources/GeoJsonOptions.java
index 79cde7429c8..bc58100e598 100644
--- a/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/sources/GeoJsonOptions.java
+++ b/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/sources/GeoJsonOptions.java
@@ -44,6 +44,17 @@ public GeoJsonOptions withBuffer(int buffer) {
return this;
}
+ /**
+ * Initialises whether to calculate line distance metrics.
+ *
+ * @param lineMetrics true to calculate line distance metrics.
+ * @return the current instance for chaining
+ */
+ public GeoJsonOptions withLineMetrics(boolean lineMetrics) {
+ this.put("lineMetrics", lineMetrics);
+ return this;
+ }
+
/**
* Douglas-Peucker simplification tolerance (higher means simpler geometries and faster performance).
*
@@ -88,5 +99,4 @@ public GeoJsonOptions withClusterRadius(int clusterRadius) {
this.put("clusterRadius", clusterRadius);
return this;
}
-
}
diff --git a/platform/android/MapboxGLAndroidSDKTestApp/src/main/AndroidManifest.xml b/platform/android/MapboxGLAndroidSDKTestApp/src/main/AndroidManifest.xml
index c87e9d09bff..e23b1d64f38 100644
--- a/platform/android/MapboxGLAndroidSDKTestApp/src/main/AndroidManifest.xml
+++ b/platform/android/MapboxGLAndroidSDKTestApp/src/main/AndroidManifest.xml
@@ -432,6 +432,17 @@
android:name="android.support.PARENT_ACTIVITY"
android:value=".activity.FeatureOverviewActivity" />
</activity>
+ <activity
+ android:name=".activity.style.GradientLineActivity"
+ android:description="@string/description_gradient_line"
+ android:label="@string/activity_gradient_line">
+ <meta-data
+ android:name="@string/category"
+ android:value="@string/category_style" />
+ <meta-data
+ android:name="android.support.PARENT_ACTIVITY"
+ android:value=".activity.FeatureOverviewActivity" />
+ </activity>
<activity
android:name=".activity.style.DataDrivenStyleActivity"
android:description="@string/description_data_driven_style"
diff --git a/platform/android/MapboxGLAndroidSDKTestApp/src/main/java/com/mapbox/mapboxsdk/testapp/activity/style/GradientLineActivity.java b/platform/android/MapboxGLAndroidSDKTestApp/src/main/java/com/mapbox/mapboxsdk/testapp/activity/style/GradientLineActivity.java
new file mode 100644
index 00000000000..f980976bf90
--- /dev/null
+++ b/platform/android/MapboxGLAndroidSDKTestApp/src/main/java/com/mapbox/mapboxsdk/testapp/activity/style/GradientLineActivity.java
@@ -0,0 +1,117 @@
+package com.mapbox.mapboxsdk.testapp.activity.style;
+
+import android.graphics.Color;
+import android.os.Bundle;
+import android.support.v7.app.AppCompatActivity;
+import com.mapbox.mapboxsdk.maps.MapView;
+import com.mapbox.mapboxsdk.maps.MapboxMap;
+import com.mapbox.mapboxsdk.maps.OnMapReadyCallback;
+import com.mapbox.mapboxsdk.style.layers.LineLayer;
+import com.mapbox.mapboxsdk.style.sources.GeoJsonOptions;
+import com.mapbox.mapboxsdk.style.sources.GeoJsonSource;
+import com.mapbox.mapboxsdk.testapp.R;
+import com.mapbox.mapboxsdk.testapp.utils.ResourceUtils;
+import timber.log.Timber;
+
+import java.io.IOException;
+
+import static com.mapbox.mapboxsdk.style.expressions.Expression.interpolate;
+import static com.mapbox.mapboxsdk.style.expressions.Expression.lineProgress;
+import static com.mapbox.mapboxsdk.style.expressions.Expression.linear;
+import static com.mapbox.mapboxsdk.style.expressions.Expression.rgb;
+import static com.mapbox.mapboxsdk.style.expressions.Expression.stop;
+import static com.mapbox.mapboxsdk.style.layers.Property.LINE_CAP_ROUND;
+import static com.mapbox.mapboxsdk.style.layers.Property.LINE_JOIN_ROUND;
+import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.lineCap;
+import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.lineColor;
+import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.lineGradient;
+import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.lineJoin;
+import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.lineWidth;
+
+/**
+ * Activity showcasing applying a gradient coloring to a line layer.
+ */
+public class GradientLineActivity extends AppCompatActivity implements OnMapReadyCallback {
+
+ public static final String LINE_SOURCE = "gradient";
+ private MapboxMap mapboxMap;
+ private MapView mapView;
+
+ @Override
+ public void onCreate(Bundle savedInstanceState) {
+ super.onCreate(savedInstanceState);
+ setContentView(R.layout.activity_gradient_line);
+
+ mapView = findViewById(R.id.mapView);
+ mapView.onCreate(savedInstanceState);
+ mapView.getMapAsync(this);
+ }
+
+ @Override
+ public void onMapReady(MapboxMap map) {
+ this.mapboxMap = map;
+
+ try {
+ String geoJson = ResourceUtils.readRawResource(GradientLineActivity.this, R.raw.test_line_gradient_feature);
+ mapboxMap.addSource(new GeoJsonSource(LINE_SOURCE, geoJson, new GeoJsonOptions().withLineMetrics(true)));
+ mapboxMap.addLayer(new LineLayer("gradient", LINE_SOURCE)
+ .withProperties(
+ lineGradient(interpolate(
+ linear(), lineProgress(),
+ stop(0f, rgb(0, 0, 255)),
+ stop(0.5f, rgb(0, 255, 0)),
+ stop(1f, rgb(255, 0, 0)))
+ ),
+ lineColor(Color.RED),
+ lineWidth(10.0f),
+ lineCap(LINE_CAP_ROUND),
+ lineJoin(LINE_JOIN_ROUND)
+ )
+ );
+ } catch (IOException exception) {
+ Timber.e(exception);
+ }
+ }
+
+ @Override
+ protected void onStart() {
+ super.onStart();
+ mapView.onStart();
+ }
+
+ @Override
+ protected void onResume() {
+ super.onResume();
+ mapView.onResume();
+ }
+
+ @Override
+ protected void onPause() {
+ super.onPause();
+ mapView.onPause();
+ }
+
+ @Override
+ protected void onStop() {
+ super.onStop();
+ mapView.onStop();
+ }
+
+ @Override
+ public void onSaveInstanceState(Bundle outState) {
+ super.onSaveInstanceState(outState);
+ mapView.onSaveInstanceState(outState);
+ }
+
+ @Override
+ public void onLowMemory() {
+ super.onLowMemory();
+ mapView.onLowMemory();
+ }
+
+ @Override
+ public void onDestroy() {
+ super.onDestroy();
+ mapView.onDestroy();
+ }
+}
diff --git a/platform/android/MapboxGLAndroidSDKTestApp/src/main/res/layout/activity_gradient_line.xml b/platform/android/MapboxGLAndroidSDKTestApp/src/main/res/layout/activity_gradient_line.xml
new file mode 100644
index 00000000000..e5db4b63df6
--- /dev/null
+++ b/platform/android/MapboxGLAndroidSDKTestApp/src/main/res/layout/activity_gradient_line.xml
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<com.mapbox.mapboxsdk.maps.MapView
+ xmlns:android="http://schemas.android.com/apk/res/android"
+ xmlns:app="http://schemas.android.com/apk/res-auto"
+ android:id="@id/mapView"
+ android:layout_width="match_parent"
+ android:layout_height="match_parent"
+ app:mapbox_cameraTargetLat="45.38301927899065"
+ app:mapbox_cameraTargetLng="8.63525390625"
+ app:mapbox_cameraZoom="7"
+ app:mapbox_styleUrl="@string/mapbox_style_mapbox_streets"/>
diff --git a/platform/android/MapboxGLAndroidSDKTestApp/src/main/res/raw/test_line_gradient_feature.geojson b/platform/android/MapboxGLAndroidSDKTestApp/src/main/res/raw/test_line_gradient_feature.geojson
new file mode 100644
index 00000000000..3525259cbad
--- /dev/null
+++ b/platform/android/MapboxGLAndroidSDKTestApp/src/main/res/raw/test_line_gradient_feature.geojson
@@ -0,0 +1,38 @@
+{
+ "type": "FeatureCollection",
+ "features": [
+ {
+ "type": "Feature",
+ "properties": {},
+ "geometry": {
+ "type": "LineString",
+ "coordinates": [
+ [
+ 9.38507080078125,
+ 46.16936992120204
+ ],
+ [
+ 9.07196044921875,
+ 45.81540082150529
+ ],
+ [
+ 9.3878173828125,
+ 45.85271700071619
+ ],
+ [
+ 9.2010498046875,
+ 45.46783598133375
+ ],
+ [
+ 8.876953125,
+ 44.422011314236634
+ ],
+ [
+ 7.635498046875,
+ 45.07352060670971
+ ]
+ ]
+ }
+ }
+ ]
+}
\ No newline at end of file
diff --git a/platform/android/MapboxGLAndroidSDKTestApp/src/main/res/values/descriptions.xml b/platform/android/MapboxGLAndroidSDKTestApp/src/main/res/values/descriptions.xml
index bb4e0cfe6d7..6c68edc4d29 100644
--- a/platform/android/MapboxGLAndroidSDKTestApp/src/main/res/values/descriptions.xml
+++ b/platform/android/MapboxGLAndroidSDKTestApp/src/main/res/values/descriptions.xml
@@ -29,6 +29,7 @@
<string name="description_dynamic_info_window_adapter">Learn how to create a dynamic custom InfoWindow</string>
<string name="description_viewpager">Use SupportMapFragments in a ViewPager</string>
<string name="description_runtime_style">Adopt the map style on the fly</string>
+ <string name="description_gradient_line">Show a gradient line layer from a geojson source</string>
<string name="description_data_driven_style">Use functions to change the map appearance</string>
<string name="description_symbol_layer">Manipulate symbols at runtime</string>
<string name="description_custom_sprite">Use a custom sprite in a Symbol Layer</string>
diff --git a/platform/android/MapboxGLAndroidSDKTestApp/src/main/res/values/titles.xml b/platform/android/MapboxGLAndroidSDKTestApp/src/main/res/values/titles.xml
index 736c33fe34e..ddf35188634 100644
--- a/platform/android/MapboxGLAndroidSDKTestApp/src/main/res/values/titles.xml
+++ b/platform/android/MapboxGLAndroidSDKTestApp/src/main/res/values/titles.xml
@@ -30,6 +30,7 @@
<string name="activity_minmax_zoom">Min/Max Zoom</string>
<string name="activity_viewpager">ViewPager</string>
<string name="activity_runtime_style">Runtime Style</string>
+ <string name="activity_gradient_line">Gradient line layer</string>
<string name="activity_data_driven_style">Data Driven Style</string>
<string name="activity_circle_layer">Circle layer</string>
<string name="activity_style_file">Local Style file</string>