maui-linux/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Issue2270.cs

using System.Collections.ObjectModel;
using Xamarin.Forms.CustomAttributes;
using Xamarin.Forms.Internals;

namespace Xamarin.Forms.Controls.TestCasesPages
{
	[Preserve (AllMembers=true)]
	[Issue (IssueTracker.Github, 2270, "NSInternalCOnsistencyException when bound to ObservableCollection", PlatformAffected.iOS)]
	public class Issue2270 : ContentPage
	{
		public Issue2270()
		{
			BindingContext = new TestListViewModel();

			Padding = new Thickness(0, 40, 0, 0);

			var btn = new Button {
				Text = "Load Data",
				BorderWidth = 1,
				BorderColor = Color.Gray,
			};
			btn.SetBinding (Button.CommandProperty, "LoadDataCommand");

			var lv = new ListView();// { IsGroupingEnabled = true };

			var dt = new DataTemplate (typeof(TextCell));
			dt.SetBinding (TextCell.TextProperty, "Name");

			lv.ItemTemplate = dt;
			lv.SetBinding (ListView.ItemsSourceProperty, "Rows");

			Content = new StackLayout {
				Children = {
					btn,
					lv
				}
			};

		}

		public class TestListViewModel
		{
			//public ObservableCollection<ObservableCollection<Row>> Rows {
			public ObservableCollection<Row> Rows {
				get;
				set;
			}

			public TestListViewModel ()
			{
				//Rows = new ObservableCollection<ObservableCollection<Row>>();
				Rows = new ObservableCollection<Row>();
			}

			Command _command;

			public Command LoadDataCommand {
				get {
					return _command ?? (_command = new Command (LoadData));
				}
			}

			void LoadData() {
				Rows.Clear ();

				foreach (var row in new[] { new Row { Name = "one" }, new Row { Name = "Two" } }) {
					Rows.Add (row);
				}
			}

		}

		public class Row
		{
			public string Name { get; set; }
		}
	}
}