public Uri getSoundUri() {
        String soundName = getSound();

        if (soundName == null || soundName.isEmpty()) return Uri.EMPTY;

        if (soundName.equals("default")) {
            return RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
        } else {
            return assetUtil.getUri(soundName, AssetUtil.RESOURCE_TYPE_RAW);
        }
    }
Sound file path for the local notification.
@return Uri of the sound file or {@link Uri.EMPTY} if not set.
src/android/Options.java