[android] #5887 - Custom layer crash fix + updated test case

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/CustomLayer.java

@@ -20,7 +20,7 @@ public class CustomLayer extends Layer {
         super(nativePtr);
     }
 
-    public void invalidate() {
+    public void update() {
         nativeUpdate();
     }
 

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/Layer.java

@@ -106,7 +106,7 @@ public abstract class Layer {
         }
     }
 
-    public void invalidate() {
+    public final void invalidate() {
         this.invalidated = true;
     }
 }

platform/android/MapboxGLAndroidSDKTestApp/src/main/java/com/mapbox/mapboxsdk/testapp/activity/customlayer/CustomLayerActivity.java

@@ -7,14 +7,17 @@ import android.support.v7.app.ActionBar;
 import android.support.v7.app.AppCompatActivity;
 import android.support.v7.widget.Toolbar;
 import android.util.Log;
+import android.view.Menu;
 import android.view.MenuItem;
 import android.view.View;
+
 import com.mapbox.mapboxsdk.camera.CameraUpdateFactory;
 import com.mapbox.mapboxsdk.geometry.LatLng;
 import com.mapbox.mapboxsdk.style.layers.CustomLayer;
 import com.mapbox.mapboxsdk.maps.MapView;
 import com.mapbox.mapboxsdk.maps.MapboxMap;
 import com.mapbox.mapboxsdk.maps.OnMapReadyCallback;
+import com.mapbox.mapboxsdk.style.layers.Layer;
 import com.mapbox.mapboxsdk.style.layers.NoSuchLayerException;
 import com.mapbox.mapboxsdk.testapp.R;
 import com.mapbox.mapboxsdk.testapp.model.customlayer.ExampleCustomLayer;
@@ -33,14 +36,7 @@ public class CustomLayerActivity extends AppCompatActivity {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_custom_layer);
 
-        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
-        setSupportActionBar(toolbar);
-
-        final ActionBar actionBar = getSupportActionBar();
-        if (actionBar != null) {
-            actionBar.setDisplayHomeAsUpEnabled(true);
-            actionBar.setDisplayShowHomeEnabled(true);
-        }
+        setupActionBar();
 
         mapView = (MapView) findViewById(R.id.mapView);
         mapView.onCreate(savedInstanceState);
@@ -80,13 +76,20 @@ public class CustomLayerActivity extends AppCompatActivity {
                     ExampleCustomLayer.createContext(),
                     ExampleCustomLayer.InitializeFunction,
                     ExampleCustomLayer.RenderFunction,
-                    ExampleCustomLayer.DeinitializeFunction), null);
+                    ExampleCustomLayer.DeinitializeFunction), "building");
             fab.setImageResource(R.drawable.ic_layers_clear_24dp);
         }
 
         isShowingCustomLayer = !isShowingCustomLayer;
     }
 
+    private void updateLayer() {
+        CustomLayer custom = mapboxMap.getLayerAs("custom");
+        if (custom != null) {
+            custom.update();
+        }
+    }
+
     @Override
     public void onResume() {
         super.onResume();
@@ -117,14 +120,34 @@ public class CustomLayerActivity extends AppCompatActivity {
         mapView.onLowMemory();
     }
 
+    @Override
+    public boolean onCreateOptionsMenu(Menu menu) {
+        getMenuInflater().inflate(R.menu.menu_custom_layer, menu);
+        return true;
+    }
+
     @Override
     public boolean onOptionsItemSelected(MenuItem item) {
         switch (item.getItemId()) {
             case android.R.id.home:
                 onBackPressed();
                 return true;
+            case R.id.action_update_layer:
+                updateLayer();
+                return true;
             default:
                 return super.onOptionsItemSelected(item);
         }
     }
+
+    private void setupActionBar() {
+        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
+        setSupportActionBar(toolbar);
+
+        final ActionBar actionBar = getSupportActionBar();
+        if (actionBar != null) {
+            actionBar.setDisplayHomeAsUpEnabled(true);
+            actionBar.setDisplayShowHomeEnabled(true);
+        }
+    }
 }

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

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<menu xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:mapbox="http://schemas.android.com/apk/res-auto">
+
+    <item
+        android:id="@+id/action_update_layer"
+        android:title="Update layer (invalidate)" />
+</menu>

platform/android/src/style/layers/custom_layer.cpp

@@ -24,6 +24,7 @@ namespace android {
     CustomLayer::~CustomLayer() = default;
 
     void CustomLayer::update(jni::JNIEnv&) {
+        Log::Debug(mbgl::Event::JNI, "Updating map");
         if (map) {
             map->update(mbgl::Update::Repaint);
         } else {