How to add a button at the end of RecyclerView?

This is what I am using in kotlin. Hope it helps somebody.

class ThumbnailsAdapter(
        private val mContext: Context,
        private val list: ArrayList<Image>
) : RecyclerView.Adapter<RecyclerView.ViewHolder>() {

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
        return when (viewType) {
            R.layout.z_thumbnail -> {
                val view = LayoutInflater.from(mContext)
                        .inflate(R.layout.z_thumbnail, parent, false)
                ThumbnailViewHolder(view)
            }
            R.layout.z_thumbanail_add -> {
                val view = LayoutInflater.from(mContext)
                        .inflate(R.layout.z_thumbanail_add, parent, false)
                PlaceholderViewHolder(view)
            }
            else -> throw IllegalArgumentException("unknown view type $viewType")
        }
    }

    override fun getItemCount(): Int {
        return list.size + 1
    }

    override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
        when (getItemViewType(position)) {
            R.layout.z_thumbnail -> (holder as ThumbnailViewHolder).bind(list[position].path)
            R.layout.z_thumbanail_add -> (holder as PlaceholderViewHolder).bind()
        }
    }

    override fun getItemViewType(position: Int): Int {
        return when (position) {
            list.size -> R.layout.z_thumbanail_add
            else -> R.layout.z_thumbnail
        }
    }

    inner class ThumbnailViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        private val imageView = itemView.findViewById<ImageView>(R.id.thumbnail)

        fun bind(path: String) {
            Glide.with(mContext).load(path).into(imageView)
        }
    }

    inner class PlaceholderViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        private val btn = itemView.findViewById<ImageView>(R.id.add_images_btn)

        fun bind() {
            btn.setOnClickListener {
                //Do your logic here for the button
            }
        }
    }

}

I came across this problem and found this answer. The current selected answer is correct but it is missing some details. Here is the full implementation,

Add this method to your adapter

@Override
public int getItemViewType(int position) {
    return (position == myItems.size()) ? R.layout.button : R.layout.item;
}

It will check if the current position is past the last item in your list, if it is then it will return the button layout value to this method,

@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

    View itemView;

    if(viewType == R.layout.item){
        itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.item, parent, false);
    }

    else {
        itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.button, parent, false);
    }

    return new MyViewHolder(itemView);
}

The above method checks if the passed viewType is the item layout or the button layout and then inflates the view occordingly and sends the inflated view to this method,

@Override
public void onBindViewHolder(MyViewHolder holder, int position) {
    if(position == myItems.size()) {
        holder.button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Toast.makeText(context, "Button Clicked", Toast.LENGTH_LONG).show();
            }
        });
    }
    else {
        final String name = myItems.get(position);
        holder.title.setText(name);
    }
}

This checks if we are past the last item in the list and if we are then it sets the onClick method to our button. Otherwise it creates an item like normal.

We also need to change the getItemCount method to this

@Override
public int getItemCount() {
    return myItems.size() + 1;
}

Since we are going through all the items and then adding a button at the end, the + 1 is our button.

Then lastly we need to add our view to the myViewHolder class

public class MyViewHolder extends RecyclerView.ViewHolder {
    public TextView title;
    public Button button;

    public MyViewHolder(View view) {
        super(view);
        title  = (TextView) view.findViewById(R.id.title);
        button = (Button) view.findViewById(R.id.bottom_button);
    }
}

I hope this helps!

One way to do it would be to make your footer view a "ViewType" of your adapter. In order to do that, overrides getItemViewType to return a different value for your last item.

@Override
public int getItemViewType(int position) {
    return (position == mData.size()) ? VIEW_TYPE_FOOTER : VIEW_TYPE_CELL;
}

Then in the onCreateViewHolder, handle the different viewType.

@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

    if (viewType == VIEW_TYPE_CELL) {

        //Create viewholder for your default cell
    }
    else {

        //Create viewholder for your footer view
    }
}

Don't forget to update the value return by getCount() by adding 1, and to distinguish the 2 types of ViewHolder in OnBindViewHolder (with instanceof for example).

Here is the trick that work for me without creating a new view layout. Basically you have to compare the size of array and position of view holder to generate a new view in onBindViewHolder.
Write the following code:

@Override
public void onBindViewHolder(final ViewHolder holder, int position) {
    //This is necessary even if you mention view gone in xml file.
    holder.mAddBtn.setVisibility(View.GONE);
    //Compare size and add button at buttom of view,ie arraylist size
    if(position==mComplaintList.size()-1){
        holder.mAddBtn.setVisibility(View.VISIBLE);
    }
    holder.mAddBtn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
        //Write code
        }
    });
}