package com.bignerdranch.android.beatbox;

import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class BeatBoxFragment extends Fragment {

    public static BeatBoxFragment newInstance() {
        return new BeatBoxFragment();
    }


    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_beat_box, container, false);

        RecyclerView recyclerView = (RecyclerView) view.findViewById(R.id.fragment_beat_box_recycler_view);
        recyclerView.setLayoutManager(new GridLayoutManager(getActivity(), 3));

        return view;
    }
}

package com.bignerdranch.android.beatbox;

import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.text.Layout;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;

public class BeatBoxFragment extends Fragment {

    public static BeatBoxFragment newInstance() {
        return new BeatBoxFragment();
    }


    @Nullable @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_beat_box, container, false);

        RecyclerView recyclerView = (RecyclerView) view.findViewById(R.id.fragment_beat_box_recycler_view);
        recyclerView.setLayoutManager(new GridLayoutManager(getActivity(), 3));

        return view;
    }


    private class SoundHolder extends RecyclerView.ViewHolder {

        private Button mButton;

        public SoundHolder(LayoutInflater inflater, ViewGroup container) {
            super(inflater.inflate(R.layout.list_item_sound, container, false);

            mButton = (Button) itemView.findViewById(R.id.list_item_sound_button);
        }
    }

    private class SoundAdapter extends RecyclerView.Adapter<SoundHolder> {

        @Override
        public SoundHolder onCreateViewHolder(ViewGroup parent, int i) {
            LayoutInflater inflater = LayoutInflater.from(getActivity());
            return new SoundHolder(inflater, parent);
        }

        @Override
        public void onBindViewHolder(SoundHolder soundHolder, int i) {

        }

        @Override
        public int getItemCount() {
            return 0;
        }
    }
}

Create adapter and viewholder for beatbox
Create adapter and viewholder for beatbox
