Adding example of onStyleImageMissing listener usage (#1070)

MapboxAndroidDemo/src/global/java/com/mapbox/mapboxandroiddemo/MainActivity.java

@@ -131,6 +131,7 @@
 import com.mapbox.mapboxandroiddemo.examples.styles.LineLayerActivity;
 import com.mapbox.mapboxandroiddemo.examples.styles.LocalStyleSourceActivity;
 import com.mapbox.mapboxandroiddemo.examples.styles.MapboxStudioStyleActivity;
+import com.mapbox.mapboxandroiddemo.examples.styles.MissingIconActivity;
 import com.mapbox.mapboxandroiddemo.examples.styles.RotatingTextAnchorPositionActivity;
 import com.mapbox.mapboxandroiddemo.examples.styles.ShowHideLayersActivity;
 import com.mapbox.mapboxandroiddemo.examples.styles.StyleFadeSwitchActivity;
@@ -648,6 +649,14 @@ private void initializeModels() {
       null,
       R.string.activity_styles_text_field_formatting_url, true, BuildConfig.MIN_SDK_VERSION));
 
+    exampleItemModels.add(new ExampleItemModel(
+            R.id.nav_styles,
+            R.string.activity_styles_missing_icon_title,
+            R.string.activity_styles_missing_icon_description,
+            new Intent(MainActivity.this, MissingIconActivity.class),
+            null,
+            R.string.activity_styles_missing_icon_url, true, BuildConfig.MIN_SDK_VERSION));
+
     exampleItemModels.add(new ExampleItemModel(
       R.id.nav_extrusions,
       R.string.activity_extrusions_population_density_extrusions_title,

MapboxAndroidDemo/src/main/AndroidManifest.xml

@@ -411,6 +411,13 @@
                 android:name="android.support.PARENT_ACTIVITY"
                 android:value="com.mapbox.mapboxandroiddemo.MainActivity" />
         </activity>
+        <activity
+            android:name=".examples.styles.MissingIconActivity"
+            android:label="@string/activity_styles_missing_icon_title">
+            <meta-data
+                android:name="android.support.PARENT_ACTIVITY"
+                android:value="com.mapbox.mapboxandroiddemo.MainActivity" />
+        </activity>
         <activity
             android:name=".examples.query.QueryFeatureActivity"
             android:label="@string/activity_query_feature_title">

MapboxAndroidDemo/src/main/java/com/mapbox/mapboxandroiddemo/examples/styles/MissingIconActivity.java

@@ -0,0 +1,187 @@
+package com.mapbox.mapboxandroiddemo.examples.styles;
+
+import android.os.Bundle;
+import android.support.annotation.NonNull;
+import android.support.v7.app.AppCompatActivity;
+
+import com.mapbox.geojson.Feature;
+import com.mapbox.geojson.FeatureCollection;
+import com.mapbox.geojson.Point;
+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.SymbolLayer;
+import com.mapbox.mapboxsdk.style.sources.GeoJsonSource;
+import com.mapbox.mapboxsdk.utils.BitmapUtils;
+
+import static com.mapbox.mapboxsdk.style.expressions.Expression.get;
+import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.iconAllowOverlap;
+import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.iconIgnorePlacement;
+import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.iconImage;
+import static com.mapbox.mapboxsdk.style.layers.PropertyFactory.textAllowOverlap;
+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.textOffset;
+
+/**
+ * Use the {@link MapView#addOnStyleImageMissingListener(MapView.OnStyleImageMissingListener)}
+ * to handle the situation where a SymbolLayer tries using a missing image as an icon. If an icon-image
+ * cannot be found in a map style, a custom image can be provided to the map via
+ * the listener.
+ */
+public class MissingIconActivity extends AppCompatActivity {
+
+  private static final String ICON_SOURCE_ID = "ICON_SOURCE_ID";
+  private static final String ICON_LAYER_ID = "ICON_LAYER_ID";
+  private static final String PROFILE_NAME = "PROFILE_NAME";
+  private static final String CARLOS = "Carlos";
+  private static final String ANTONY = "Antony";
+  private static final String MARIA = "Maria";
+  private static final String LUCIANA = "Luciana";
+  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_styles_missing_icon);
+
+    mapView = findViewById(R.id.mapView);
+    mapView.onCreate(savedInstanceState);
+    mapView.getMapAsync(new OnMapReadyCallback() {
+      @Override
+      public void onMapReady(@NonNull final MapboxMap mapboxMap) {
+
+        // Add Features which represent the location of each profile photo SymbolLayer icon
+        Feature carlosFeature = Feature.fromGeometry(Point.fromLngLat(-7.9760742,
+          41.2778064));
+        carlosFeature.addStringProperty(PROFILE_NAME, CARLOS);
+
+        Feature antonyFeature = Feature.fromGeometry(Point.fromLngLat(-8.0639648,
+          37.5445773));
+        antonyFeature.addStringProperty(PROFILE_NAME, ANTONY);
+
+        Feature mariaFeature = Feature.fromGeometry(Point.fromLngLat(-9.1845703,
+          38.9764924));
+        mariaFeature.addStringProperty(PROFILE_NAME, MARIA);
+
+        Feature lucianaFeature = Feature.fromGeometry(Point.fromLngLat(-7.5146484,
+          40.2459915));
+        lucianaFeature.addStringProperty(PROFILE_NAME, LUCIANA);
+
+        // Use a URL to build and add a Style object to the map. Then add a source to the Style.
+        mapboxMap.setStyle(
+          new Style.Builder().fromUrl(Style.LIGHT)
+            .withSource(new GeoJsonSource(ICON_SOURCE_ID,
+              FeatureCollection.fromFeatures(new Feature[] {
+                carlosFeature,
+                antonyFeature,
+                mariaFeature,
+                lucianaFeature}))),
+          new Style.OnStyleLoaded() {
+            @Override
+            public void onStyleLoaded(@NonNull Style style) {
+              MissingIconActivity.this.mapboxMap = mapboxMap;
+
+              // Add a SymbolLayer to the style. iconImage is set to a value that will
+              // be used later in the addOnStyleImageMissingListener below
+              style.addLayer(new SymbolLayer(ICON_LAYER_ID, ICON_SOURCE_ID).withProperties(
+                iconImage(get(PROFILE_NAME)),
+                iconIgnorePlacement(true),
+                iconAllowOverlap(true),
+                textField(get(PROFILE_NAME)),
+                textIgnorePlacement(true),
+                textAllowOverlap(true),
+                textOffset(new Float[] {0f, 2f})
+              ));
+            }
+          });
+      }
+    });
+
+    // Use the listener to match the id with the appropriate person. The correct profile photo is
+    // given to the map during "runtime".
+    mapView.addOnStyleImageMissingListener(new MapView.OnStyleImageMissingListener() {
+      @Override
+      public void onStyleImageMissing(@NonNull String id) {
+        switch (id) {
+          case CARLOS:
+            addImage(id, R.drawable.carlos);
+            break;
+          case ANTONY:
+            addImage(id, R.drawable.antony);
+            break;
+          case MARIA:
+            addImage(id, R.drawable.maria);
+            break;
+          case LUCIANA:
+            addImage(id, R.drawable.luciana);
+            break;
+          default:
+            addImage(id, R.drawable.carlos);
+            break;
+        }
+      }
+    });
+  }
+
+  private void addImage(String id, int drawableImage) {
+    Style style = mapboxMap.getStyle();
+    if (style != null) {
+      style.addImageAsync(id, BitmapUtils.getBitmapFromDrawable(
+        getResources().getDrawable(drawableImage)));
+    }
+  }
+
+  // Add the mapView lifecycle to the activity's lifecycle methods
+  @Override
+  public void onResume() {
+    super.onResume();
+    mapView.onResume();
+  }
+
+  @Override
+  protected void onStart() {
+    super.onStart();
+    mapView.onStart();
+  }
+
+  @Override
+  protected void onStop() {
+    super.onStop();
+    mapView.onStop();
+  }
+
+  @Override
+  public void onPause() {
+    super.onPause();
+    mapView.onPause();
+  }
+
+  @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);
+  }
+}

MapboxAndroidDemo/src/main/res/layout/activity_styles_missing_icon.xml

@@ -0,0 +1,18 @@
+<?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=".examples.styles.MissingIconActivity">
+
+    <com.mapbox.mapboxsdk.maps.MapView
+        android:id="@+id/mapView"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        mapbox:mapbox_cameraTargetLat="39.6226149"
+        mapbox:mapbox_cameraTargetLng="-8.4155273"
+        mapbox:mapbox_cameraZoom="6"/>
+
+</FrameLayout>

MapboxAndroidDemo/src/main/res/values/descriptions_strings.xml

@@ -35,6 +35,7 @@
     <string name="activity_styles_transparent_background_description">Create a transparent background and fill it with something such as moving water.</string>
     <string name="activity_styles_click_to_add_image_description">Select a photo on the device and add it on the map tap location.</string>
     <string name="activity_styles_rotating_anchor_text_description">Adjust the anchor position of SymbolLayer text fields.</string>
+    <string name="activity_styles_missing_icon_description">Provide an icon when a Style failed to load one.</string>
     <string name="activity_extrusions_catalina_marathon_extrusions_description">Use data-driven styling and GeoJSON data to set extrusions\' heights.</string>
     <string name="activity_extrusions_population_density_extrusions_description">Use extrusions to display 3D building height based on imported vector data.</string>
     <string name="activity_extrusions_adjust_extrusions_description">Change the location and color of the light shined on extrusions.</string>

MapboxAndroidDemo/src/main/res/values/titles_strings.xml

@@ -32,6 +32,7 @@
     <string name="activity_styles_transparent_background_title">Transparent render surface</string>
     <string name="activity_styles_click_to_add_image_title">Click to add photo</string>
     <string name="activity_styles_rotating_anchor_text_title">Text anchor position</string>
+    <string name="activity_styles_missing_icon_title">Style with missing icon</string>
     <string name="activity_extrusions_catalina_marathon_extrusions_title">Use GeoJSON data to set extrusion height</string>
     <string name="activity_extrusions_population_density_extrusions_title">Display 3D building height based on vector data</string>
     <string name="activity_extrusions_adjust_extrusions_title">Adjust light location and color</string>

MapboxAndroidDemo/src/main/res/values/urls_strings.xml

@@ -34,6 +34,7 @@
     <string name="activity_styles_transparent_background_url" translatable="false">https://i.imgur.com/5bYnlp5.png</string>
     <string name="activity_styles_click_to_add_image_url" translatable="false">https://i.imgur.com/uPIH5Ck.png</string>
     <string name="activity_styles_rotating_anchor_text_url" translatable="false">https://i.imgur.com/w8cP6Wn.png</string>
+    <string name="activity_styles_missing_icon_url" translatable="false">https://i.imgur.com/lSk2tDB.png</string>
     <string name="activity_extrusions_population_density_extrusions_url" translatable="false">http://i.imgur.com/se1z8Wb.png</string>
     <string name="activity_extrusions_catalina_marathon_extrusions_url" translatable="false">http://i.imgur.com/6j848JL.jpg</string>
     <string name="activity_extrusions_adjust_extrusions_url" translatable="false">http://i.imgur.com/XNTyIO5.png</string>