@Override public void draw(final CountDownLatch latch){
  if (!initialized) {
    return;
  }
  if (isShowing()) {
    canvasRenderer.draw();
  }
  if (latch != null) {
    latch.countDown();
  }
}

@ Override public void draw ( final CountDownLatch latch ) { if ( ! initialized ) { return ; } if ( isShowing ( ) ) { canvasRenderer . draw ( ) ; } if ( latch != null ) { latch . countDown ( ) ; } }
draw the scene for this canvas
