ArticleDataset.java

  public static class ArticleDataset {

    private static final int DAYS_PRIOR = 20;
    SortedList<Article> sortedList = null;

    public ArticleDataset(final RecyclerView recyclerView, final RecyclerView.Adapter adapter) {
      this.sortedList = new SortedList<>(Article.class,
          new SortedList.BatchedCallback<>(new SortedListAdapterCallback<Article>(adapter) {
            @Override public int compare(Article a1, Article a2) {
              return a1.compare(a2);
            }

            @Override public boolean areContentsTheSame(Article oldItem, Article newItem) {
              return oldItem.areContentsTheSame(newItem);
            }

            @Override public boolean areItemsTheSame(Article item1, Article item2) {
              return item1.areItemsTheSame(item2);
            }

            @Override public void onInserted(int position, int count) {
              super.onInserted(position, count);
              recyclerView.scrollToPosition(position);
            }
          }));
    }

    public void generateRandom() {
      List<Article> articleList = new ArrayList<>();
      for (int i = 0; i < DAYS_PRIOR; i++) {
        articleList.add(
            Article.builder().publishedTime(DateTime.now().minusDays(i).getMillis()).build());
      }
      sortedList.beginBatchedUpdates();
      sortedList.addAll(articleList);
      sortedList.endBatchedUpdates();
    }

    public int size() {
      return sortedList.size();
    }

    public Article getArticle(int position) {
      return sortedList.get(position);
    }

    public void remove(Article article) {
      sortedList.beginBatchedUpdates();
      sortedList.remove(article);
      sortedList.endBatchedUpdates();
    }

    public void add(Article article) {
      sortedList.beginBatchedUpdates();
      sortedList.add(article);
      sortedList.endBatchedUpdates();
    }
  }