Add TranslucentMapActivity demo

Author: matteblair

tangramdemos/src/main/AndroidManifest.xml

@@ -51,6 +51,11 @@
             android:label="@string/simplemap_title"
             android:exported="true"
             android:parentActivityName=".DemoMainActivity"/>
+        <activity
+            android:name=".TranslucentMapActivity"
+            android:label="@string/translucency_title"
+            android:exported="true"
+            android:parentActivityName=".DemoMainActivity"/>
     </application>
 
 </manifest>

tangramdemos/src/main/java/com/mapzen/tangramdemos/DemoDetails.java

@@ -52,5 +52,6 @@ public Class<? extends AppCompatActivity> getActivityClass() {
             new DemoDetails(R.string.markers_title, R.string.markers_detail, MarkersActivity.class),
             new DemoDetails(R.string.multimap_title, R.string.multimap_detail, MultiMapActivity.class),
             new DemoDetails(R.string.sceneupdates_title, R.string.sceneupdates_detail, SceneUpdatesActivity.class),
+            new DemoDetails(R.string.translucency_title, R.string.translucency_detail, TranslucentMapActivity.class),
     };
 }

tangramdemos/src/main/java/com/mapzen/tangramdemos/TranslucentMapActivity.java

@@ -0,0 +1,94 @@
+package com.mapzen.tangramdemos;
+
+import android.os.Bundle;
+import android.widget.ImageView;
+
+import androidx.appcompat.app.ActionBar;
+import androidx.appcompat.app.AppCompatActivity;
+
+import com.mapzen.tangram.MapController;
+import com.mapzen.tangram.MapView;
+import com.mapzen.tangram.SceneUpdate;
+import com.mapzen.tangram.networking.HttpHandler;
+import com.mapzen.tangram.viewholder.GLViewHolderFactory;
+import com.mapzen.tangram.viewholder.TextureViewHolderFactory;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class TranslucentMapActivity extends AppCompatActivity implements MapView.MapReadyCallback {
+
+    // MapController is the main class used to interact with a Tangram map.
+    MapController map;
+
+    // MapView is the View used to display the map.
+    MapView view;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_translucency);
+
+        // Set up back button to return to the demo list.
+        ActionBar actionBar = getSupportActionBar();
+        if (actionBar != null) {
+            actionBar.setDisplayHomeAsUpEnabled(true);
+        }
+
+        // Our MapView is declared in the layout file.
+        view = (MapView)findViewById(R.id.map);
+
+        // Lifecycle events from the Activity must be forwarded to the MapView.
+        view.onCreate(savedInstanceState);
+
+        // Create an HttpHandler to cache map tiles.
+        HttpHandler httpHandler = new CachingHttpHandler(getExternalCacheDir());
+
+        // Create a factory to build a TextureView with translucency enabled.
+        GLViewHolderFactory factory = new TextureViewHolderFactory(true);
+
+        // Start a background process to set up the map.
+        view.getMapAsync(this, factory, httpHandler);
+    }
+
+    @Override
+    public void onMapReady(MapController mapController) {
+        // We receive a MapController object in this callback when the map is ready for use.
+        map = mapController;
+
+        // Set our API key as a scene update.
+        List<SceneUpdate> updates = new ArrayList<>();
+        updates.add(new SceneUpdate("global.sdk_api_key", BuildConfig.NEXTZEN_API_KEY));
+
+        // Update the scene background color to be translucent.
+        updates.add(new SceneUpdate("scene.background.color", "[0, 0, 0, 0]"));
+
+        map.loadSceneFileAsync("bubble-wrap/bubble-wrap-style.yaml", updates);
+    }
+
+    // Below are the remaining Activity lifecycle events that must be forwarded to our MapView.
+
+    @Override
+    public void onResume() {
+        super.onResume();
+        view.onResume();
+    }
+
+    @Override
+    public void onPause() {
+        super.onPause();
+        view.onPause();
+    }
+
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+        view.onDestroy();
+    }
+
+    @Override
+    public void onLowMemory() {
+        super.onLowMemory();
+        view.onLowMemory();
+    }
+}

tangramdemos/src/main/res/layout/activity_translucency.xml

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<RelativeLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="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=".SimpleMapActivity">
+
+    <ImageView
+        android:id="@+id/imageView"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:background="#FFD180"
+        android:contentDescription="@null"
+        android:scaleType="center"
+        app:srcCompat="@drawable/mapzen_logo" />
+
+    <com.mapzen.tangram.MapView
+        android:id="@+id/map"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"/>
+</RelativeLayout>

tangramdemos/src/main/res/values/strings.xml

@@ -14,6 +14,8 @@
     <string name="sceneupdates_detail">Modify the scene file on the fly</string>
     <string name="simplemap_title">Simple Map</string>
     <string name="simplemap_detail">Basic map sample</string>
+    <string name="translucency_title">Translucent Map</string>
+    <string name="translucency_detail">Render a map with translucency</string>
     <string name="wtc">World Trade Center</string>
     <string name="esb">Empire State Building</string>
     <string name="cpz">Central Park Zoo</string>