Avalonia/src/Avalonia.Base/Rendering/Composition/Server/ServerList.cs

using System;
using System.Collections.Generic;
using Avalonia.Rendering.Composition.Transport;

// Special license applies <see href="https://raw.githubusercontent.com/AvaloniaUI/Avalonia/master/src/Avalonia.Base/Rendering/Composition/License.md">License.md</see>

namespace Avalonia.Rendering.Composition.Server
{
    /// <summary>
    /// A server-side list container capable of receiving changes from the UI thread
    /// Right now it's quite dumb since it always receives the full list
    /// </summary>
    class ServerList<T> : ServerObject where T : ServerObject
    {
        public List<T> List { get; } = new List<T>();

        protected override void DeserializeChangesCore(BatchStreamReader reader, TimeSpan committedAt)
        {
            if (reader.Read<byte>() == 1)
            {
                List.Clear();
                var count = reader.Read<int>();
                for (var c = 0; c < count; c++) 
                    List.Add(reader.ReadObject<T>());
            }
            base.DeserializeChangesCore(reader, committedAt);
        }

        public override long LastChangedBy
        {
            get
            {
                var seq = base.LastChangedBy;
                foreach (var i in List)
                    seq = Math.Max(i.LastChangedBy, seq);
                return seq;
            }
        }

        public List<T>.Enumerator GetEnumerator() => List.GetEnumerator();

        public ServerList(ServerCompositor compositor) : base(compositor)
        {
        }
    }
}