przyklad

using System;
using System.Collections.Generic;
using System.Windows.Forms;

namespace WykopTest
{
    public partial class Form1 : Form
    {
        private readonly List<string> firstList;
        private readonly List<string> secondList;
        private int _actualList = 1;

        public Form1()
        {
            firstList = new List<string> {"AAAA", "BBBB"};
            secondList = new List<string> {"CCCC", "DDDD"};
            InitializeComponent();
            AddItems(listView1, firstList);
        }

        private void AddItems(ListView list, IEnumerable<string> items)
        {
            list.Items.Clear();
            foreach (var item in items)
            {
                list.Items.Add(item);
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            if (_actualList == 1)
            {
                AddItems(listView1, secondList);
                _actualList = 2;
            }
            else
            {
                AddItems(listView1, firstList);
                _actualList = 1;
            }
        }
    }
}