public Bitmap pop(long timeout,TimeUnit unit) throws InterruptedException {
  checkNotMainThread();
  ensureScheduled();
  return finished.poll(timeout,unit);
}

public Bitmap pop ( long timeout , TimeUnit unit ) throws InterruptedException { checkNotMainThread ( ) ; ensureScheduled ( ) ; return finished . poll ( timeout , unit ) ; }
returns a previously drawn frame from this drawable or null , if no drawable can be popped right now . this function has a timeout
