SingleListAdapter.java

package com.example.radit.akb48.adapter;

import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;

import com.example.radit.akb48.R;
import com.example.radit.akb48.model.Single;


import java.util.ArrayList;
import java.util.List;



/**
 * Created by adit on 30/11/18.
 */
public class SingleListAdapter extends RecyclerView.Adapter<SingleListAdapter.SingleViewHolder>{

    private List<Single> singleList;
    private OnGridItemSelectedListener onGridItemSelectedListener;

    public SingleListAdapter(OnGridItemSelectedListener onGridItemSelectedListener) {
        this.onGridItemSelectedListener = onGridItemSelectedListener;
        singleList = new ArrayList<>();
    }

    private void add(Single item) {
        singleList.add(item);
        notifyItemInserted(singleList.size() - 1);
    }

    public void addAll(List<Single> singleList) {
        for (Single single : singleList) {
            add(single);
        }
    }

    public void remove(Single item) {
        int position = singleList.indexOf(item);
        if (position > -1) {
            singleList.remove(position);
            notifyItemRemoved(position);
        }
    }

    public void clear() {
        while (getItemCount() > 0) {
            remove(getItem(0));
        }
    }

    public Single getItem(int position){
        return singleList.get(position);
    }

    @Override
    public SingleViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item_single, parent, false);
        final SingleViewHolder singleViewHolder = new SingleViewHolder(view);

        singleViewHolder.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                int adapterPos = singleViewHolder.getAdapterPosition();
                if (adapterPos != RecyclerView.NO_POSITION) {
                    if (onGridItemSelectedListener != null) {
                        onGridItemSelectedListener.onGridItemClick(singleViewHolder.itemView, adapterPos);
                    }
                }
            }
        });

        return singleViewHolder;
    }

    @Override
    public void onBindViewHolder(SingleViewHolder holder, int position) {
        final Single single = singleList.get(position);

        holder.img.setImageResource(single.getImg());
        holder.title.setText(single.getTitle());
    }

    @Override
    public int getItemCount() {
        return singleList.size();
    }

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

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

    public class SingleViewHolder extends RecyclerView.ViewHolder {

        ImageView img;
        TextView title;

        public SingleViewHolder(View itemView) {
            super(itemView);

            img = (ImageView) itemView.findViewById(R.id.img);
            title = (TextView) itemView.findViewById(R.id.title);
        }

    }

    public interface OnGridItemSelectedListener {
        void onGridItemClick(View v, int position);
    }

}