如何从列表Xamarin Forms中获取所选项目？

Question

我查询了我的表以获取我的SQLite数据库中的数据列表。我可以列出这些项目，但我无法得到我选择的内容。我尝试使用DisplayAlert显示我选择的内容。我怎样才能得到我选择的内容？下面是我获取数据的SQLite表（tblCaf）。 GetActivity（）函数是查询。

[Table("tblCaf")]
public class CAFTable
{
    [MaxLength(100)]
    public string CAFNo { get; set; }
    [MaxLength(100)]
    public string TempCAFNo { get; set; }
    [MaxLength(100)]
    public string EmployeeID { get; set; }
    public DateTime CAFDate { get; set; }
    [MaxLength(100)]
    public string CustomerID { get; set; }
    public DateTime StartTime { get; set; }
    public DateTime EndTime { get; set; }
    public string Photo1 { get; set; }
    public string Photo2 { get; set; }
    public string Photo3 { get; set; }
    [MaxLength(1000)]
    public string Remarks { get; set; }
    [MaxLength(1000)]
    public string OtherConcern { get; set; }
}

public void GetActivity()
    {
        try
        {
            var db = DependencyService.Get<ISQLiteDB>();
            var conn = db.GetConnection();

            var getCaf = conn.QueryAsync<CAFTable>("SELECT CAFNo, CAFDate FROM tblCaf WHERE CAFNo != '' ORDER BY CAFDate DESC");
            var resultCount = getCaf.Result.Count;

            if (resultCount > 0)
            {
                var result = getCaf.Result;
                lstActivityHistory.ItemsSource = result;
            }
        }
        catch (Exception ex)
        {
            DisplayAlert("Data Error", ex.Message, "Ok");
        }
    }

private void lstActivityHistory_ItemSelected(object sender, SelectedItemChangedEventArgs e)
    {
        var caf = e.SelectedItem as CAFTable;
        DisplayAlert("Selected", caf.CustomerID, "ok");
    }