How to use data for RecyclerView adapter and split them into different groups by parameter?

I have used Nested RecyclerView for this purpose.

Maybe not the best technique to achieve such layout. But it works somehow

MainActivity.xml (Headers)

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout     
   xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:app="http://schemas.android.com/apk/res-auto"
   xmlns:tools="http://schemas.android.com/tools"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   tools:context=".Activities.MainActivity">

<android.support.v7.widget.RecyclerView
    android:id="@+id/rvMain"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    tools:listitem="@layout/row"
    />

</android.support.constraint.ConstraintLayout>

MainActivity.java inside onCreate() (Headers)

    rvMain = findViewById(R.id.rvMain);
    ArrayList<Row> dataList = new ArrayList<>();
    myAdapter = new RowAdapter(MainActivity.this, dataList);
    RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(MainActivity.this);
    rvMain.setLayoutManager(layoutManager);
    rvMain.addItemDecoration(new DividerItemDecoration(MainActivity.this, LinearLayoutManager.VERTICAL));
    rvMain.setAdapter(myAdapter);

Row for MainActivity RecyclerView

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="match_parent"
   android:layout_height="wrap_content"
   xmlns:tools="http://schemas.android.com/tools"
   xmlns:app="http://schemas.android.com/apk/res-auto"
   android:padding="11dp">

<TextView
    android:id="@+id/tvAlbumNumber"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="Album 1"
    android:textColor="#000"
    android:textSize="21sp"
    android:textStyle="bold"
    android:typeface="monospace"
    />

<android.support.v7.widget.RecyclerView
    android:id="@+id/rvAlbums"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_below="@+id/tvAlbumNumber"
    android:layout_marginTop="3dp"
    tools:listitem="@layout/row_albums"
    />

</RelativeLayout>

* I put RecyclerView insied Row to have multiple items in it.

MainActivity RowAdapter

public class RowAdapter extends RecyclerView.Adapter<RowAdapter.ViewHolder>{
   public  ArrayList<Row> arrayList;
   public Context context;
   int albumPos;

public RowAdapter(Context context, ArrayList<Row> arrayList) {
    this.arrayList = arrayList;
    this.context = context;
}

@NonNull
@Override
public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
    View view = LayoutInflater.from((parent.getContext())).inflate(R.layout.row, parent, false);
    return new ViewHolder(view);
}

@Override
public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
    holder.tvAlbumNumber.setText("Album "+arrayList.get(position).getAlbumId());

    AlbumAdapter myAlbumAdapter = new AlbumAdapter(context, arrayList.get(position).getData());
    holder.rvAlbums.setLayoutManager(new LinearLayoutManager(context));
    holder.rvAlbums.setItemAnimator(new DefaultItemAnimator());
    holder.rvAlbums.addItemDecoration(new DividerItemDecoration(context,LinearLayoutManager.VERTICAL));
    holder.rvAlbums.setAdapter(myAlbumAdapter);
}

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

class ViewHolder extends RecyclerView.ViewHolder {
    TextView tvAlbumNumber;
    RecyclerView rvAlbums;

    public ViewHolder(View itemView) {
        super(itemView);
        tvAlbumNumber = itemView.findViewById(R.id.tvAlbumNumber);
        rvAlbums = itemView.findViewById(R.id.rvAlbums);
    }
  }
}

Inside onBindViewHolder I called the RecyclerView to fill the items in first header

Items Adapter (AlbumAdapter) (Items)

public class AlbumAdapter extends RecyclerView.Adapter<AlbumAdapter.AlbumViewHolder> {
    public ArrayList<RowAlbums> arrayList;
    private Context context;

AlbumAdapter(Context context, ArrayList<RowAlbums> arrayList) {
    this.context = context;
    this.arrayList = arrayList;
}

@NonNull
@Override
public AlbumViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
    View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.row_albums, parent, false);
    return new AlbumViewHolder(view);
}

@Override
public void onBindViewHolder(@NonNull AlbumViewHolder holder, int position) {
    Picasso.get().load(arrayList.get(position).getImgUrl())
            .placeholder(R.drawable.user).error(R.drawable.user).into(holder.imgUser);
    holder.tvId.setText(arrayList.get(position).getId());
    holder.tvTitle.setText(arrayList.get(position).getTitle());
}

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

class AlbumViewHolder extends RecyclerView.ViewHolder {
    TextView tvId, tvTitle;
    ImageView imgUser;

    public AlbumViewHolder(final View itemView) {
        super(itemView);
        tvId = itemView.findViewById(R.id.tvId);
        tvTitle = itemView.findViewById(R.id.tvTitle);
        imgUser = itemView.findViewById(R.id.imgUser);

        itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(context, arrayList.get(getAdapterPosition()).getTitle(), Toast.LENGTH_SHORT).show();
            }
        });
      }
    }
}

You have to make JSON like below and parse it using Hashmap

    {
  "Header1": [
    {
      "name": "Itemtype1"
    },
    {
      "name": "Itemtype2"
    } 
  ],
"Header2": [
    {
      "name": "Itemtype1"
    },
    {
      "name": "Itemtype2"
    } 
  ],
 "Header3": [
    {
      "name": "Itemtype1"
    },
    {
      "name": "Itemtype2"
    } 
  ]
}

check this example