MainActivity.java

package com.example.mylist;

import android.os.Bundle;
import android.widget.Button;

import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {
    private RecyclerView rcvItems;
    private Button btnOK;

    private ArrayList<Item> data;
    private MyAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        rcvItems = findViewById(R.id.rcvItems);
        btnOK = findViewById(R.id.btnOK);

        data = new ArrayList<>();

        data.add(new Item("Saleh", 10));
        data.add(new Item("Ali", 15));
        data.add(new Item("Amneh", 20));
        data.add(new Item("Saleh", 10));
        data.add(new Item("Ali", 15));
        data.add(new Item("Amneh", 20));
        data.add(new Item("Saleh", 10));
        data.add(new Item("Ali", 15));
        data.add(new Item("Amneh", 20));
        data.add(new Item("Saleh", 10));
        data.add(new Item("Ali", 15));
        data.add(new Item("Amneh", 20));
        data.add(new Item("Saleh", 10));
        data.add(new Item("Ali", 15));
        data.add(new Item("Amneh", 20));
        data.add(new Item("Saleh", 10));
        data.add(new Item("Ali", 15));
        data.add(new Item("Amneh", 20));
        data.add(new Item("Saleh", 10));
        data.add(new Item("Ali", 15));
        data.add(new Item("Amneh", 20));
        data.add(new Item("Saleh", 10));
        data.add(new Item("Ali", 15));
        data.add(new Item("Amneh", 20));


        adapter = new MyAdapter(data);
        RecyclerView.LayoutManager manager = new LinearLayoutManager(this);

        rcvItems.setLayoutManager(manager);
        rcvItems.setAdapter(adapter);

    }
}