private void AddedToOuter(int outerIndex, ReadOnlyObservableCollection <T> inner)
{
var handler = inner?.AddChangeHandlers <ReadOnlyObservableCollection <T>, T>(
(index, item) => this.AddedToInner(inner, index, item),
(index, item) => this.RemovedFromInner(inner, index),
() => this.ClearedInner(inner));
this.unsubscribeCallbacks.Insert(outerIndex, () => Unsubscribe(inner, handler));
}
internal FilterCollection(
ReadOnlyObservableCollection <T> originalItems, Predicate <T> predicate, IComparer <T> comparer)
{
this.predicate = predicate ?? throw new ArgumentNullException(nameof(predicate));
this.comparer = comparer;
var handler = originalItems.AddChangeHandlers <ReadOnlyObservableCollection <T>, T>(
this.InsertIfMatch, this.Remove, this.Clear);
this.RegisterForRemoval(originalItems, handler);
}
