title: GLSurfaceView not appearing over MapView
body: <p>My goal is to use OpenGL ES 2.0 with Google Maps. I would like to create an app that follows the user as they are traveling from point A to point B. I realize that this can be done using Google Maps addPolyline to draw a line, but I want to use OpenGL instead in order to show overlap of paths. I'm currently receiving an error which is due to incorrectly setting up the GLSurfaceView. </p>
  
  <p>My code in the GoogleMapsTracker class is as follows:</p>
  
  <pre><code>private MapView mapView;
  private GoogleMap map;
  private GLSurfaceView mGLSurfaceView;
  
  /**
   * Use this factory method to create a new instance of
   * this fragment using the provided parameters.
   */
  public static GoogleMapsTracker newInstance() {
      GoogleMapsTracker fragment = new GoogleMapsTracker();
      fragment.setRetainInstance(true);
      return fragment;
  }
  
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
  
      mapView = (MapView) getActivity().findViewById(R.id.map);
      mGLSurfaceView = new GLSurfaceView(getActivity());
  
      // Check if the system supports OpenGL ES 2.0
      final ActivityManager am = (ActivityManager) getActivity().getSystemService(Context.ACTIVITY_SERVICE);
      final ConfigurationInfo cInfo = am.getDeviceConfigurationInfo();
      final boolean supportsEs2 = cInfo.reqGlEsVersion &gt;= 0x20000;
  
      if(supportsEs2){
          // Request an OpenGL ES 2.0 compatible context
          mGLSurfaceView.setEGLContextClientVersion(2);
  
          // Set the renderer to out demo renderer, defined below
          mGLSurfaceView.setRenderer(new GoogleMapsRenderer(getActivity()));
      } else {
          // This is where you could create an OpenGL ES1.x compatible
          // renderer if you wanted to support both ES 1 and ES 2
          Log.d("Does Not Support ES 2.0", "Does NOT Support ES 2.0");
      }
  }
  
  @Override
  public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
      View v;
  
      if(SettingsActivity.mUnits){
          v = inflater.inflate(R.layout.google_maps_tracker_metric, container, false);
      } else {
          v = inflater.inflate(R.layout.google_maps_tracker, container, false);
      }
  
      // Gets the MapView from the XML layout and creates it
      mapView = (MapView) v.findViewById(R.id.map);
      mapView.onCreate(savedInstanceState);
  
      // Gets to GoogleMap from the MapView and does initialization stuff
      map = mapView.getMap();
  
      map.getUiSettings().setMyLocationButtonEnabled(true);
      map.getUiSettings().setZoomControlsEnabled(true);
      map.getUiSettings().setRotateGesturesEnabled(true);
  
      map.setMyLocationEnabled(true);
  
      map.setMapType(GoogleMap.MAP_TYPE_SATELLITE);
  
      // Needs to call MapsInitializer before doing any CameraUpdateFactory calls
      MapsInitializer.initialize(this.getActivity());
  
      // Updates the location and zoom of the MapView
      CameraUpdate cameraUpdate = CameraUpdateFactory.newLatLngZoom(new LatLng(45.669656, -111.067373), 18);
      map.animateCamera(cameraUpdate);
  
      mGLSurfaceView = (GLSurfaceView) v.findViewById(R.id.gl);
      mGLSurfaceView.setEGLContextClientVersion(2);
      GoogleMapsRenderer renderer = new GoogleMapsRenderer(getActivity());
      mGLSurfaceView.setEGLConfigChooser(8, 8, 8, 8, 16, 0);
      mGLSurfaceView.setRenderer(renderer);
      mGLSurfaceView.getHolder().setFormat(PixelFormat.TRANSLUCENT);
      mGLSurfaceView.setRenderMode(GLSurfaceView.RENDERMODE_CONTINUOUSLY);
  
      mGLSurfaceView.setZOrderOnTop(true);
  
      return v;
  }
  </code></pre>
  
  <p>My XML code:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;RelativeLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:orientation="horizontal" &gt;
  
  &lt;!--fragment
      android:name="com.google.android.gms.maps.MapFragment"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:id="@+id/map"
      tools:context=".MainActivity" /--&gt;
  
  &lt;com.google.android.gms.maps.MapView android:id="@+id/map"
      android:layout_width="fill_parent"
      android:layout_height="fill_parent"/&gt;
  
  &lt;android.opengl.GLSurfaceView
      android:id="@+id/gl"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      class="com.example.tracker.GoogleMapsRenderer"/&gt;
  
  &lt;/RelativeLayout&gt;
  </code></pre>
  
  <p>The error I'm receiving is as follows:</p>
  
  <pre><code>    05-22 11:02:34.854  22996-22996/com.example.tracker E/AndroidRuntime﹕ FATAL     EXCEPTION: main
      Process: com.example.tracker, PID: 22996
      java.lang.NullPointerException: Attempt to invoke virtual method 'void android.opengl.GLSurfaceView$GLThread.surfaceCreated()' on a null object reference
              at android.opengl.GLSurfaceView.surfaceCreated(GLSurfaceView.java:523)
              at android.view.SurfaceView.updateWindow(SurfaceView.java:580)
              at android.view.SurfaceView$3.onPreDraw(SurfaceView.java:176)
              at android.view.ViewTreeObserver.dispatchOnPreDraw(ViewTreeObserver.java:944)
              at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1970)
              at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1061)
              at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5885)
              at android.view.Choreographer$CallbackRecord.run(Choreographer.java:767)
              at android.view.Choreographer.doCallbacks(Choreographer.java:580)
              at android.view.Choreographer.doFrame(Choreographer.java:550)
              at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:753)
              at android.os.Handler.handleCallback(Handler.java:739)
              at android.os.Handler.dispatchMessage(Handler.java:95)
              at android.os.Looper.loop(Looper.java:135)
              at android.app.ActivityThread.main(ActivityThread.java:5254)
              at java.lang.reflect.Method.invoke(Native Method)
              at java.lang.reflect.Method.invoke(Method.java:372)
              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
  </code></pre>
  
  <p>I'm quite certain that I'm not adding my views together properly. If anyone can point out my mistakes and a better way of implementing this idea that would be much appreciated.</p>