package starpunk;

import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.Screen;
import com.badlogic.gdx.graphics.GL10;

public class GameScreen
  implements Screen
{
  @Override
  public void render( final float delta )
  {
    Gdx.gl10.glClear( GL10.GL_COLOR_BUFFER_BIT );
  }

  @Override
  public void resize( int width, int height )
  {
  }

  @Override
  public void show()
  {
  }

  @Override
  public void hide()
  {
  }

  @Override
  public void pause()
  {
  }

  @Override
  public void resume()
  {
  }

  @Override
  public void dispose()
  {
  }
}

package starpunk;

import com.badlogic.gdx.Screen;

public class GameScreen
  implements Screen
{
  @Override
  public void render( final float delta )
  {
  }

  @Override
  public void resize( int width, int height )
  {
  }

  @Override
  public void show()
  {
  }

  @Override
  public void hide()
  {
  }

  @Override
  public void pause()
  {
  }

  @Override
  public void resume()
  {
  }

  @Override
  public void dispose()
  {
  }
}

--- 
+++ 
@@ -1,6 +1,8 @@
 package starpunk;
 
+import com.badlogic.gdx.Gdx;
 import com.badlogic.gdx.Screen;
+import com.badlogic.gdx.graphics.GL10;
 
 public class GameScreen
   implements Screen
@@ -8,6 +10,7 @@
   @Override
   public void render( final float delta )
   {
+    Gdx.gl10.glClear( GL10.GL_COLOR_BUFFER_BIT );
   }
 
   @Override
Clear the screen on render
