using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Collections.Specialized;
using System.ComponentModel;
using System.Threading;

public class AsyncObservableCollection<T> : ObservableCollection<T>
{
    private SynchronizationContext _synchronizationContext = SynchronizationContext.Current;

    public AsyncObservableCollection()
    {
    }

    public AsyncObservableCollection(IEnumerable<T> list)
        : base(list)
    {
    }

    protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
    {
        if (SynchronizationContext.Current == _synchronizationContext)
        {
            // Execute the CollectionChanged event on the current thread
            RaiseCollectionChanged(e);
        }
        else
        {
            // Post the CollectionChanged event on the creator thread
            _synchronizationContext.Send(RaiseCollectionChanged, e);
        }
    }

    private void RaiseCollectionChanged(object param)
    {
        // We are in the creator thread, call the base implementation directly
        base.OnCollectionChanged((NotifyCollectionChangedEventArgs)param);
    }

    protected override void OnPropertyChanged(PropertyChangedEventArgs e)
    {
        if (SynchronizationContext.Current == _synchronizationContext)
        {
            // Execute the PropertyChanged event on the current thread
            RaisePropertyChanged(e);
        }
        else
        {
            // Post the PropertyChanged event on the creator thread
            _synchronizationContext.Post(RaisePropertyChanged, e);
        }
    }

    private void RaisePropertyChanged(object param)
    {
        // We are in the creator thread, call the base implementation directly
        base.OnPropertyChanged((PropertyChangedEventArgs)param);
    }
}