/**
  * Called when the item is assumed to be gone for good. Remove the graphic annotation from the
  * overlay.
  */
 @Override
 public void onDone() {
   mOverlay.remove(mGraphic);
 }
 /**
  * Hide the graphic when the corresponding object was not detected. This can happen for
  * intermediate frames temporarily, for example if the object was momentarily blocked from view.
  */
 @Override
 public void onMissing(Detector.Detections<Barcode> detectionResults) {
   mOverlay.remove(mGraphic);
 }