@Override
  public void onShutterButtonClick(ShutterButton b) {
    if (isContinuousModeActive) {
      onShutterButtonPressContinuous();
    } else {
      if (handler != null) {
        handler.shutterButtonClick();
      }
    }
  }
Request the viewfinder to be invalidated.
OCRTest/src/main/java/edu/sfsu/cs/orange/ocr/CaptureActivity.java