[android] - update symbol layer example with changing symbol location

Author: tobrun

platform/android/MapboxGLAndroidSDKTestApp/src/main/java/com/mapbox/mapboxsdk/testapp/activity/style/ZoomFunctionSymbolLayerActivity.java

@@ -4,6 +4,8 @@
 import android.os.Bundle;
 import android.support.annotation.NonNull;
 import android.support.v7.app.AppCompatActivity;
+import android.view.Menu;
+import android.view.MenuItem;
 
 import com.google.gson.JsonObject;
 import com.mapbox.mapboxsdk.geometry.LatLng;
@@ -48,6 +50,9 @@ public class ZoomFunctionSymbolLayerActivity extends AppCompatActivity {
   private MapboxMap mapboxMap;
   private GeoJsonSource source;
 
+  private boolean isInitialPosition = true;
+  private boolean isSelected = false;
+
   @Override
   public void onCreate(Bundle savedInstanceState) {
     super.onCreate(savedInstanceState);
@@ -59,15 +64,15 @@ public void onCreate(Bundle savedInstanceState) {
       @Override
       public void onMapReady(@NonNull final MapboxMap map) {
         mapboxMap = map;
-        updateSource(false);
+        updateSource();
         addLayer();
         addMapClickListener();
       }
     });
   }
 
-  private void updateSource(boolean selected) {
-    FeatureCollection featureCollection = createFeatureCollection(selected);
+  private void updateSource() {
+    FeatureCollection featureCollection = createFeatureCollection();
     if (source != null) {
       source.setGeoJson(featureCollection);
     } else {
@@ -76,11 +81,15 @@ private void updateSource(boolean selected) {
     }
   }
 
-  private FeatureCollection createFeatureCollection(boolean selected) {
-    Point point = Point.fromCoordinates(Position.fromCoordinates(-74.016181, 40.701745));
+  private FeatureCollection createFeatureCollection() {
+    Position position = isInitialPosition
+      ? Position.fromCoordinates(-74.01618140, 40.701745)
+      : Position.fromCoordinates(-73.988097, 40.749864);
+
+    Point point = Point.fromCoordinates(position);
     Feature feature = Feature.fromGeometry(point);
     JsonObject properties = new JsonObject();
-    properties.addProperty(KEY_PROPERTY_SELECTED, selected);
+    properties.addProperty(KEY_PROPERTY_SELECTED, isSelected);
     feature.setProperties(properties);
     return FeatureCollection.fromFeatures(new Feature[] {feature});
   }
@@ -119,14 +128,30 @@ public void onMapClick(@NonNull LatLng point) {
         if (!featureList.isEmpty()) {
           Feature feature = featureList.get(0);
           boolean isSelected = feature.getBooleanProperty(KEY_PROPERTY_SELECTED);
-          updateSource(!isSelected);
+          ZoomFunctionSymbolLayerActivity.this.isSelected = !isSelected;
+          updateSource();
         } else {
           Timber.e("No features found");
         }
       }
     });
   }
 
+  @Override
+  public boolean onCreateOptionsMenu(Menu menu) {
+    getMenuInflater().inflate(R.menu.menu_symbols, menu);
+    return true;
+  }
+
+  @Override
+  public boolean onOptionsItemSelected(MenuItem item) {
+    if (mapboxMap != null && item.getItemId() == R.id.menu_action_change_location) {
+      isInitialPosition = !isInitialPosition;
+      updateSource();
+    }
+    return super.onOptionsItemSelected(item);
+  }
+
   @Override
   protected void onStart() {
     super.onStart();

platform/android/MapboxGLAndroidSDKTestApp/src/main/res/menu/menu_symbols.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<menu xmlns:android="http://schemas.android.com/apk/res/android"
+      xmlns:app="http://schemas.android.com/apk/res-auto">
+    <item
+        android:id="@+id/menu_action_change_location"
+        android:title="@string/menuitem_change_location"
+        app:showAsAction="never"/>
+</menu>

platform/android/MapboxGLAndroidSDKTestApp/src/main/res/values/actions.xml

@@ -11,6 +11,7 @@
     <string name="menuitem_title_change_location_source_mock">Change to mock location source</string>
     <string name="menuitem_title_change_location_source_null">Reset location source to null</string>
     <string name="menuitem_change_icon_overlap">Toggle icon overlap</string>
+    <string name="menuitem_change_location">Change location</string>
     <string name="button_camera_move">Move</string>
     <string name="button_camera_ease">Ease</string>
     <string name="button_camera_animate">Animate</string>