MyContentPage.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

using Xamarin.Forms;

namespace ListViewDemoVS
{
    class MyContentPage : ContentPage
    {
        public MyContentPage()
        {
            Padding = new Thickness(0, Device.OnPlatform(20, 0, 0), 0, 0);

            ListView listView = new ListView();
            listView.ItemsSource = new ListItem[] {
                new ListItem { Title = "First", Description = "1st", Source="one.jpg" },
                new ListItem { Title = "Second", Description = "2nd", Source="two.jpg" },
                new ListItem { Title = "Third", Description = "3rd", Source="three.jpg" }
            };

            listView.ItemTemplate = new DataTemplate(typeof(ImageCell));
            listView.ItemTemplate.SetBinding(ImageCell.TextProperty, "Title");
            listView.ItemTemplate.SetBinding(ImageCell.DetailProperty, "Description");
            listView.ItemTemplate.SetBinding(ImageCell.ImageSourceProperty, "Source");
            /*
                        listView.ItemTapped += async (sender, e) =>
                        {
                            await DisplayAlert("Tapped", e.Item.ToString(), "OK");
                            ((ListView)sender).SelectedItem = null;
                        };
            */
            listView.ItemSelected += async (sender, e) =>
            {
                if (e.SelectedItem == null) return;
                ListItem item = (ListItem)e.SelectedItem;
                await DisplayAlert("Selected", ((ListItem)(e.SelectedItem)).Title, "OK");
                ((ListView)sender).SelectedItem = null;
            };

            this.Content = listView;
        }
    }
}