dependencies {
    implementation 'com.jaychang:simplerecyclerview:2.0.5'
    // for kotlin android extensions
    implementation 'com.jaychang:simplerecyclerview-kotlin-android-extensions:2.0.5'
}

/**
 * Accept two type arguments,
 * 1st is the data model this cell represents, 2nd is the view holder.
 * */
public class BookCell extends SimpleCell<Book, BookCell.ViewHolder> {

  /** 
   * Mandatory constructor, pass your data model as argument 
   * */
  public BookCell(Book item) {
    super(item);
  }

  /**
   * Define the layout resource of this cell
   * */
  @Override
  protected int getLayoutRes() {
    return R.layout.cell_book;
  }

  @NonNull
  @Override
  protected ViewHolder onCreateViewHolder(ViewGroup parent, View cellView) {
    return new ViewHolder(cellView);
  }

  @Override
  protected void onBindViewHolder(ViewHolder holder, int position, Context context, Object payload) {
    holder.textView.setText(getItem().getTitle());
  }
  
  /**
   * Optional
   * */
  @Override
  protected void onUnbindViewHolder(ViewHolder holder) {
    // do your cleaning jobs here when the item view is recycled.
  }

  /**
   * Define your view holder, which must extend SimpleViewHolder.
   * */
  static class ViewHolder extends SimpleViewHolder {
    TextView textView;

    ViewHolder(View itemView) {
      super(itemView);
      textView = itemView.findViewById(R.id.textView);
    }
  }

}

List<Book> books = DataUtils.getBooks();
List<BookCell> cells = new ArrayList<>();

for (Book book : books) {
  BookCell cell = new BookCell(book);
  // There are two default cell listeners: OnCellClickListener<T> and OnCellLongClickListener<T>
  cell.setOnCellClickListener(new SimpleCell.OnCellClickListener<Book>() {
    @Override
    public void onCellClicked(Book item) {
      ...
    }
  });
  cell.setOnCellLongClickListener(new SimpleCell.OnCellLongClickListener<Book>() {
    @Override
    public void onCellLongClicked(Book item) {
      ...
    }
  });
  cells.add(cell);
}

simpleRecyclerView.addCells(cells);

List<Book> books = DataUtils.getBooks();
List<Ad> ads = DataUtils.getAds();
List<SimpleCell> cells = new ArrayList<>();

for (Book book : books) {
  BookCell cell = new BookCell(book);
  cells.add(cell);
}

for (Ad ad : ads) {
  BookAdCell cell = new BookAdCell(ad);
  int position = (ads.indexOf(ad) + 1) * 3;
  // take up full row
  cell.setSpanSize(simpleRecyclerView.getGridSpanCount());
  cells.add(position, cell);
}

simpleRecyclerView.addCells(cells);

public interface Updatable<T> {

  boolean areContentsTheSame(T newItem);

  Object getChangePayload(T newItem);

}

public class BookCell extends SimpleCell<Book, BookCell.ViewHolder>
  implements Updatable<Book> {

  ...

  @Override
  protected void onBindViewHolder(ViewHolder holder, int position, Context context, Object payload) {
    if (payload != null) {
      // partial update
      if (payload instanceof Bundle) {
        Bundle bundle = ((Bundle) payload);
        for (String key : bundle.keySet()) {
          if (KEY_TITLE.equals(key)) {
            holder.textView.setText(bundle.getString(key));
          }
        }
      }
      return;
    }
    ...
  }
  
  /**
   * If the titles of books are same, no need to update the cell, onBindViewHolder() will not be called.
   */
  @Override
  public boolean areContentsTheSame(Book newItem) {
    return getItem().getTitle().equals(newItem.getTitle());
  }

  /**
   * If getItem() is the same as newItem (i.e. their return value of getItemId() are the same)
   * and areContentsTheSame()  return false, then the cell need to be updated,
   * onBindViewHolder() will be called with this payload object.
   * */
  @Override
  public Object getChangePayload(Book newItem) {
    Bundle bundle = new Bundle();
    bundle.putString(KEY_TITLE, newItem.getTitle());
    return bundle;
  }
  
  ...
}

SectionHeaderProvider<Book> sectionHeaderProvider = new SimpleSectionHeaderProvider<Book>() {
  // Your section header view here
  @NonNull
  @Override
  public View getSectionHeaderView(Book item, int position) {
    View view = LayoutInflater.from(SectionHeaderActivity.this).inflate(R.layout.view_section_header, null, false);
    TextView textView = (TextView) view.findViewById(R.id.textView);
    textView.setText(String.format(getString(R.string.category), item.getCategoryName()));
    return view;
  }
  // Your grouping logic here
  @Override
  public boolean isSameSection(Book item, Book nextItem) {
    return item.getCategoryId() == nextItem.getCategoryId();
  }

  // Optional, whether the header is sticky, default false
  @Override
  public boolean isSticky() {
    return stickyCheckbox.isChecked();
  }

  // Optional, top margin of each section header
  @Override
  public int getSectionHeaderMarginTop(Book item, int position) {
    return position == 0 ? 0 : Utils.dp2px(SectionHeaderActivity.this, 16);
  }
};

simpleRecyclerView.setSectionHeader(sectionHeaderProvider);

// if the total beneath hidden cells count <= 4 and shouldLoadMore() is true, onLoadMore() will be called. Default threshold is 0.
simpleRecyclerView.setAutoLoadMoreThreshold(4);

simpleRecyclerView.setOnLoadMoreListener(new OnLoadMoreListener() {
  @Override
  public boolean shouldLoadMore() {
    return hasMoreData;
  }
  
  @Override
  public void onLoadMore() {
    loadBooks();
  }
});

simpleRecyclerView.setLoadMoreToTop(true);

DragAndDropCallback<Book> dragAndDropCallback = new DragAndDropCallback<Book>() {
  // Optional, return false if you manipulate custom drag effect in the rest of callbacks.
  @Override
  public boolean enableDefaultRaiseEffect() {
    // default return true
    return super.enableDefaultRaiseEffect();
  }

  // Optional
  @Override
  public void onCellDragStarted(SimpleRecyclerView simpleRecyclerView, View itemView, Book item, int position) {
    resultView.setText("Started dragging " + item);
  }

  // Optional
  @Override
  public void onCellMoved(SimpleRecyclerView simpleRecyclerView, View itemView, Book item, int fromPosition, int toPosition){
    resultView.setText("Moved " + item + " from " + fromPosition + " to " + toPosition);
  }

  // Optional
  @Override
  public void onCellDropped(SimpleRecyclerView simpleRecyclerView, View itemView, Book item, int fromPosition, int toPosition) {
    resultView.setText("Dragged " + item + " from " + fromPosition + " to " + toPosition);
  }

  // Optional
  @Override
  public void onCellDragCancelled(SimpleRecyclerView simpleRecyclerView, View itemView, Book item, int currentPosition) {
    resultView.setText("Cancelled dragging " + item);
  }
};

simpleRecyclerView.enableDragAndDrop(R.id.dragHandle, dragAndDropCallback); 
// or
simpleRecyclerView.enableDragAndDrop(dragAndDropCallback);

SwipeToDismissCallback<Book> swipeToDismissCallback = new SwipeToDismissCallback<Book>() {
  // Optional, return false if you manipulate custom swipe effect in the rest of callbacks.
  @Override
  public boolean enableDefaultFadeOutEffect() {
    // default return true
    return super.enableDefaultFadeOutEffect();
  }

  // Optional
  @Override
  public void onCellSwiping(SimpleRecyclerView simpleRecyclerView, View itemView, Book item, int position, Canvas canvas, float dX, float dY, boolean isControlledByUser) {
    resultView.setText("Item " + item + " is swiping.");
  }

  // Optional
  @Override
  public void onCellSettled(SimpleRecyclerView simpleRecyclerView, View itemView, Book item, int position) {
    resultView.setText("Item " + item + " is settled.");
  }

  // Optional
  @Override
  public void onCellDismissed(SimpleRecyclerView simpleRecyclerView, Book item, int position) {
    resultView.setText("Item: " + item + " is dismissed.");
  }
};

// enable swipe left or right to dismiss
simpleRecyclerView.enableSwipeToDismiss(swipeToDismissCallback, LEFT, RIGHT);