public void toggleFavorite(OCFile file, boolean isFavorite) {
    file.setFavorite(isFavorite);
    mFileActivity.getStorageManager().saveFile(file);

    /// register the OCFile instance in the observer service to monitor local updates
    Intent observedFileIntent =
        FileObserverService.makeObservedFileIntent(
            mFileActivity, file, mFileActivity.getAccount(), isFavorite);
    mFileActivity.startService(observedFileIntent);

    /// immediate content synchronization
    if (file.isFavorite()) {
      syncFile(file);
    }
  }