Cyclic Adapter: An Android RecyclerView Adapter that supports endless cyclical scrolling

CyclicAdapter.java

import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.RecyclerView.Adapter;
import android.support.v7.widget.RecyclerView.AdapterDataObserver;
import android.support.v7.widget.RecyclerView.ViewHolder;
import android.view.ViewGroup;

import java.util.List;

/** 
  * This Adapter class wraps another Adapter in order to support cyclical scrolling.
  * As the user scrolls, the same list of items in the wrapped adapter will be repeated indefinitely.
  *
  * You may choose to force the RecyclerView to scroll to the middle of the list when it is first created,
  * so that the user can scroll both left and right. Otherwise the list will start at position 0, and it will
  * only be cyclical if the user scrolls right.
  *
  * One issue with this approach is that any adapter changes will only trigger view updates in the initial set
  * of items. It is not recommended to use this if you have to update adapter content. If that is needed, it
  * could potentially be supported by modifying the observerDelegate to also notify the changes at all cyclic
  * intervals.
  */
public class CyclicAdapter extends RecyclerView.Adapter {

  private final Adapter adapter;

  /** Pass in an adapter to wrap. This nested adapter should contain whatever you want to show */
  public CyclicAdapter(RecyclerView.Adapter adapter) {
    this.adapter = adapter;

    super.setHasStableIds(adapter.hasStableIds());
    super.registerAdapterDataObserver(observerDelegate);
  }

  public int getActualItemCount() {
    return adapter.getItemCount();
  }

  /**
   * Do Not Use!!!
   * <p>
   * This returns {@link Integer#MAX_VALUE} in order to create an infinite looping adapter.
   * <p>
   * Use {@link #getActualItemCount()} instead.
   */
  @Override
  public int getItemCount() {
    return Integer.MAX_VALUE;
  }

  private int adjustedPosition(int position) {
    return position % getActualItemCount();
  }

  @Override
  public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    return adapter.onCreateViewHolder(parent, viewType);
  }

  @Override
  public void onBindViewHolder(ViewHolder holder, int position) {
    adapter.onBindViewHolder(holder, adjustedPosition(position));
  }

  @Override
  public void onBindViewHolder(ViewHolder holder, int position, List payloads) {
    adapter.onBindViewHolder(holder, adjustedPosition(position), payloads);
  }

  @Override
  public int getItemViewType(int position) {
    return adapter.getItemViewType(adjustedPosition(position));
  }

  @Override
  public void setHasStableIds(boolean hasStableIds) {
    super.setHasStableIds(hasStableIds);
    adapter.setHasStableIds(hasStableIds);
  }

  @Override
  public long getItemId(int position) {
    return adapter.getItemId(adjustedPosition(position));
  }

  @Override
  public void onViewRecycled(ViewHolder holder) {
    adapter.onViewRecycled(holder);
  }

  @Override
  public boolean onFailedToRecycleView(ViewHolder holder) {
    return adapter.onFailedToRecycleView(holder);
  }

  @Override
  public void onViewAttachedToWindow(ViewHolder holder) {
    adapter.onViewAttachedToWindow(holder);
  }

  @Override
  public void onViewDetachedFromWindow(ViewHolder holder) {
    adapter.onViewDetachedFromWindow(holder);
  }

  @Override
  public void onAttachedToRecyclerView(RecyclerView recyclerView) {
    adapter.onAttachedToRecyclerView(recyclerView);
  }

  @Override
  public void onDetachedFromRecyclerView(RecyclerView recyclerView) {
    adapter.onDetachedFromRecyclerView(recyclerView);
  }

  @Override
  public void registerAdapterDataObserver(AdapterDataObserver observer) {
    adapter.registerAdapterDataObserver(observer);
  }

  @Override
  public void unregisterAdapterDataObserver(AdapterDataObserver observer) {
    adapter.unregisterAdapterDataObserver(observer);
  }

  private final AdapterDataObserver observerDelegate = new AdapterDataObserver() {
    @Override
    public void onChanged() {
      adapter.notifyDataSetChanged();
    }

    @Override
    public void onItemRangeChanged(int positionStart, int itemCount) {
      adapter.notifyItemRangeChanged(adjustedPosition(positionStart), itemCount);
    }

    @Override
    public void onItemRangeChanged(int positionStart, int itemCount, Object payload) {
      adapter.notifyItemRangeChanged(adjustedPosition(positionStart), itemCount, payload);
    }

    @Override
    public void onItemRangeInserted(int positionStart, int itemCount) {
      adapter.notifyItemRangeInserted(adjustedPosition(positionStart), itemCount);
    }

    @Override
    public void onItemRangeRemoved(int positionStart, int itemCount) {
      adapter.notifyItemRangeRemoved(adjustedPosition(positionStart), itemCount);
    }

    @Override
    public void onItemRangeMoved(int fromPosition, int toPosition, int itemCount) {
      // Unsupported
    }
  };
}