title: LibGDX not running render() method
body: <p>I'm experiencing a problem using LibGDX. </p>
  
  <p>I have a <code>Screen</code> and in its <code>render</code> method I have:</p>
  
  <pre><code>public class LoadingScreen implements Screen{
  private OrthographicCamera guiCam;
  private TankChallenge tankChallenge;
  private SpriteBatch batcher;
  private GL10 OpenGL;
  
  public LoadingScreen(TankChallenge tankChallenge) {
      this.tankChallenge=tankChallenge;
      Gdx.graphics.setTitle("RobotChallange Beta - Loading");
  
      float AR = Gdx.graphics.getHeight()/Gdx.graphics.getWidth();
      guiCam = new OrthographicCamera(10,10 * AR);
      guiCam.position.set(10f/2,AR*10f/2,0);
      batcher = new SpriteBatch();
  
      OpenGL = Gdx.graphics.getGL10();
      //loadAssets();
  }
  
  @Override
  public void render(float delta) {
      OpenGL.glClearColor(1, 0.5f, 1, 1);
      OpenGL.glClear(GL10.GL_COLOR_BUFFER_BIT);
  
      System.out.print("e");
      guiCam.update();
      Sprite sp = new Sprite();
      sp.setColor(1f,1f,0, 1);
      sp.setSize(100,100);
      sp.setOrigin(20, 0);
  
      batcher.setProjectionMatrix(guiCam.combined);
      batcher.begin();
      batcher.disableBlending();
      sp.draw(batcher);
      batcher.end();
  }
  </code></pre>
  
  <p>I call this by setting it in the implementes <code>ApplicationListener</code> class. I know it is arriving the LoadingScreen because Title is actually set to "RobotChallenge Beta - Loading".</p>