public static void UnSubscribe(this INotifyCollectionChanged n, Action <NotifierPropertyChangedEventArgs> action,
IList <string> targets)
{
if (CollectionHandlers.TryRemove(Tuple.Create(action, targets), out NotifyCollectionChangedEventHandler h))
{
if (targets.Count > 1)
{
if (n is IList oldItems)
{
foreach (var item in oldItems)
{
if (targets.Count > 1)
{
var newTargets = targets.Skip(1).ToArray();
if (item is INotifyCollectionChanged oldCollection)
{
oldCollection.UnSubscribe(action, newTargets);
}
if (item is INotifyPropertyChanged oldValue)
{
oldValue.UnSubscribe(action, newTargets);
}
}
action(new NotifierPropertyChangedEventArgs("Item", item, null));
}
}
}
n.CollectionChanged -= h;
}
}
/// <summary>
/// Registers a collection handler which provides support for a certain type
/// or multiple types of collections.
/// </summary>
/// <param name="handler">the collection handler</param>
public void RegisterCollectionHandler(CollectionHandler handler)
{
CollectionHandlers.Insert(0, handler);
}
