RxRecyclerData

private ArrayList<WeekModel> mDataList = new ArrayList<>();

//Implementation in use
private void fetchData() {
        mDisposable.add(mWeekService.getLessons()
                .subscribeOn(Schedulers.io()) 
                .observeOn(AndroidSchedulers.mainThread()) 
                .map(new Function<WeekResponse, List<WeekModel>>() {
                    @Override
                    public List<WeekModel> apply(
                            @io.reactivex.annotations.NonNull final WeekResponse response)
                            throws Exception {
                        return response.getResult();
                    }

                })
                .subscribe(new Consumer<List<WeekModel>>() {
                    @Override
                    public void accept(
                            @io.reactivex.annotations.NonNull final List<WeekModel> lessonList)
                            throws Exception {

                            mLessons.addAll(lessonList);
                            mWeekAdapter.set(mDataList);
                    }

                })
        );

    }
    
    
    
    
    
    //From medium article.
    private ExampleNetwork mExampleNetwork;

private void getDetails(String id) {
    mExampleNetwork.getCachedDetails(id) // From Cache
        .doFinally(() -> {
            mExampleNetwork
              .getDetails(id) // From Network
              .subscribe(details -> onDetailsReceived(details), this::onError);
        })
        .subscribe(details -> onDetailsReceived(details), this::onError);
}

private void onDetailsReceived(Details details) {
    if (mDetails == null || !mDetails.equals(details)) { // Implement equals with your criteria
        mDetails = details;
        updateUI();
    }
}