Torch/Torch/Collections/ObservableDictionary.cs

using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Threading;

namespace Torch.Collections
{
    [Serializable]
    public class ObservableDictionary<TKey, TValue> : Dictionary<TKey, TValue>, INotifyCollectionChanged, INotifyPropertyChanged
    {
        /// <inheritdoc />
        public new void Add(TKey key, TValue value)
        {
            base.Add(key, value);
            var kv = new KeyValuePair<TKey, TValue>(key, value);
            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, kv));
        }

        /// <inheritdoc />
        public new bool Remove(TKey key)
        {
            if (!ContainsKey(key))
                return false;

            var kv = new KeyValuePair<TKey, TValue>(key, this[key]);
            base.Remove(key);
            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, kv));
            return true;
        }

        private void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
        {
            NotifyCollectionChangedEventHandler collectionChanged = CollectionChanged;
            if (collectionChanged != null)
                foreach (NotifyCollectionChangedEventHandler nh in collectionChanged.GetInvocationList())
                {
                    var dispObj = nh.Target as DispatcherObject;

                    var dispatcher = dispObj?.Dispatcher;
                    if (dispatcher != null && !dispatcher.CheckAccess())
                    {
                        dispatcher.BeginInvoke(
                            (Action)(() => nh.Invoke(this, new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset))),
                            DispatcherPriority.DataBind);
                        continue;
                    }

                    nh.Invoke(this, e);
                }
        }


        /// <inheritdoc />
        public event NotifyCollectionChangedEventHandler CollectionChanged;

        /// <inheritdoc />
        public event PropertyChangedEventHandler PropertyChanged;
    }
}