@Nullable @Override public Bundle call(@NonNull final String method, @Nullable final String arg, @Nullable final Bundle extras) {
		return forward(() -> {
			final Bundle result = mResolver.call(new Uri.Builder().scheme("content").authority(mTargetAuthority).build(), method, arg, extras);
			if (result != null) {
				final Uri uri = result.getParcelable(EXTRA_URI);
				if (uri != null) result.putParcelable(EXTRA_URI, toProxyUri(uri));
			}
			return result;
		});
	}
This single-user provider serves as a proxy provider, since it can be accessed from any user.

Created by Oasis on 2017/8/29.
fileprovider/src/main/java/com/oasisfeng/island/fileprovider/ShuttleProvider.java