timer1.Tick -= selectItems;
            timer1.Tick += selectItems;

        private int Count = 0;

        public Form1()
        {
            InitializeComponent();
            listDrivers.ItemSelectionChanged += ListDriversOnItemSelectionChanged;
        }

        private void ListDriversOnItemSelectionChanged(object sender, ListViewItemSelectionChangedEventArgs args)
        {
            if (args.IsSelected)
            {
                Task.Factory
                    .StartNew<bool>(DoLongOperation)
                    .ContinueWith(t => DoAfterLongOperation(args.Item, t.Result), TaskScheduler.FromCurrentSynchronizationContext());

                this.Text = "Count: " + Count++;
            }            
        }

        private bool DoLongOperation()
        {
            Thread.Sleep(250);
            var isNeedLightSomeLabel = Convert.ToBoolean(DateTime.Now.Millisecond % 2);
            return isNeedLightSomeLabel;
        }

        private void DoAfterLongOperation(ListViewItem item, bool isNeedLightSomeLabel)
        {
            if (isNeedLightSomeLabel)
                item.BackColor = Color.Blue;
            else
                item.BackColor = Color.White;
        }

timer1.Tick += selectItems;

        public Form1()
        {
            InitializeComponent();

            timer1.Enabled = false;
            timer1.Interval = 250;
            timer1.Tick += selectItems;
        }

        private void onChangeIndex(object sender, EventArgs e)
        {
            timer1.Enabled = true;
        }