ObservableCollections/sandbox/WpfApp/MainWindow.xaml.cs

using ObservableCollections;
using R3;
using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Diagnostics;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Windows.Threading;

namespace WpfApp
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        //ObservableList<int> list;
        //public INotifyCollectionChangedSynchronizedView<int> ItemsView { get; set; }




        public MainWindow()
        {
            InitializeComponent();


            R3.WpfProviderInitializer.SetDefaultObservableSystem(x =>
            {
                Trace.WriteLine(x);
            });

            this.DataContext = new ViewModel();

            // Dispatcher.BeginInvoke(


            //list = new ObservableList<int>();
            //list.AddRange(new[] { 1, 10, 188 });
            //ItemsView = list.CreateSortedView(x => x, x => x, comparer: Comparer<int>.Default).ToNotifyCollectionChanged();


            //BindingOperations.EnableCollectionSynchronization(ItemsView, new object());
        }

        //int adder = 99;

        //private void Button_Click(object sender, RoutedEventArgs e)
        //{
        //    ThreadPool.QueueUserWorkItem(_ =>
        //    {
        //        list.Add(adder++);
        //    });
        //}

        //protected override void OnClosed(EventArgs e)
        //{
        //    ItemsView.Dispose();
        //}
    }

    public class ViewModel
    {
        private ObservableList<int> observableList { get; } = new ObservableList<int>();
        public INotifyCollectionChangedSynchronizedView<int> ItemsView { get; }
        public ReactiveCommand<Unit> AddCommand { get; } = new ReactiveCommand<Unit>();
        public ReactiveCommand<Unit> InsertAtRandomCommand { get; } = new ReactiveCommand<Unit>();
        public ReactiveCommand<Unit> RemoveAtRandomCommand { get; } = new ReactiveCommand<Unit>();
        public ReactiveCommand<Unit> ClearCommand { get; } = new ReactiveCommand<Unit>();
        public ReactiveCommand<Unit> ReverseCommand { get; } = new ReactiveCommand<Unit>();
        public ReactiveCommand<Unit> SortCommand { get; } = new ReactiveCommand<Unit>();
        public ReactiveCommand<Unit> AttachFilterCommand { get; } = new ReactiveCommand<Unit>();
        public ReactiveCommand<Unit> ResetFilterCommand { get; } = new ReactiveCommand<Unit>();

        public ViewModel()
        {
            observableList.Add(1);
            observableList.Add(2);

            var view = observableList.CreateView(x => x);
            ItemsView = view.ToNotifyCollectionChanged(SynchronizationContextCollectionEventDispatcher.Current);


            // check for optimize list
            // ItemsView = observableList.ToNotifyCollectionChanged(SynchronizationContextCollectionEventDispatcher.Current);


            AddCommand.Subscribe(_ =>
            {
                ThreadPool.QueueUserWorkItem(_ =>
                {
                    observableList.Add(Random.Shared.Next());
                });
            });

            InsertAtRandomCommand.Subscribe(_ =>
            {
                var from = Random.Shared.Next(0, view.Count);
                observableList.Insert(from, Random.Shared.Next());
            });

            RemoveAtRandomCommand.Subscribe(_ =>
            {
                var from = Random.Shared.Next(0, view.Count);
                observableList.RemoveAt(from);
            });

            ClearCommand.Subscribe(_ =>
            {
                observableList.Clear();
            });


            ReverseCommand.Subscribe(_ =>
            {
                observableList.Reverse();
            });

            SortCommand.Subscribe(_ =>
            {
                observableList.Sort();
            });

            AttachFilterCommand.Subscribe(_ =>
            {
                view.AttachFilter(x => x % 2 == 0);
            });

            ResetFilterCommand.Subscribe(_ =>
            {
                view.ResetFilter();
            });
        }
    }

    public class WpfDispatcherCollection(Dispatcher dispatcher) : ICollectionEventDispatcher
    {
        public void Post(CollectionEventDispatcherEventArgs ev)
        {
            dispatcher.InvokeAsync(() =>
            {
                ev.Invoke();
            });
        }
    }
}