RxJava & DiffUtil

RxJavaAndDiffUtil.java

private void subscribeToData() {
  Flowable<List<Data>> dataLists = Flowable
      .interval(0, 3, TimeUnit.SECONDS, Schedulers.computation())
      .map(val -> {
        Log.d(TAG, "Shuffling original list...");
        return Data.shuffle(originalList).subList(0, (int) (0.8 * originalList.size()));
      })
      .share();

  Flowable<List<Data>> startWith = dataLists
      .startWith(new ArrayList<Data>(originalList));

  this.disposable = Flowable
      .zip(startWith, dataLists, (current, next) -> {
        Log.d(TAG, "Calculate diff result...");
        MyCallback callback = new MyCallback(current, next);
        DiffUtil.DiffResult diffResult = DiffUtil.calculateDiff(callback, true);
        return Pair.create(diffResult, next);
      })
      .observeOn(AndroidSchedulers.mainThread())
      .subscribe(diffResultListPair -> {
        Log.d(TAG, "Update adapter!");
        adapter.setDataList(diffResultListPair.second);
        diffResultListPair.first.dispatchUpdatesTo(adapter);
      });
}