private void UpdateItem(OrderedListInternal <int, T> filterCollection, NotifyCollectionChangedEventArgs e, NotificationType notificationType)
{
int filterIndex;
switch (e.Action)
{
case NotifyCollectionChangedAction.Add:
var item = (T)e.NewItems[0];
UpdateFilterItems(filterCollection, e.NewStartingIndex, 1);
if (!_filter(item))
{
return;
}
filterIndex = filterCollection.Add(e.NewStartingIndex, item);
OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, item, filterIndex), notificationType);
break;
case NotifyCollectionChangedAction.Remove:
filterIndex = filterCollection.IndexOfKey(e.OldStartingIndex);
UpdateFilterItems(filterCollection, e.OldStartingIndex, -1);
if (filterIndex == -1)
{
return;
}
filterCollection.RemoveAt(filterIndex);
OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, e.OldItems[0], filterIndex), notificationType);
break;
case NotifyCollectionChangedAction.Replace:
filterIndex = filterCollection.IndexOfKey(e.NewStartingIndex);
if (filterIndex == -1)
{
return;
}
var newItem = (T)e.NewItems[0];
if (_filter(newItem))
{
T oldItem = filterCollection.GetValue(filterIndex);
filterCollection.Values[filterIndex] = newItem;
OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Replace, e.NewItems[0], oldItem, filterIndex), notificationType);
}
else
{
T oldValue = filterCollection.GetValue(filterIndex);
filterCollection.RemoveAt(filterIndex);
OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, oldValue, filterIndex), notificationType);
}
break;
default:
UpdateFilterInternal(filterCollection, _filter, notificationType);
break;
}
}
/// <summary>
/// Updates a filter.
/// </summary>
protected virtual void UpdateFilterInternal(out bool shouldRaiseEvents)
{
FilterDelegate <T> currentFilter = _filter;
if (currentFilter != null)
{
_filterCollection.Clear();
for (int index = 0; index < Items.Count; index++)
{
T item = Items[index];
if (currentFilter(item))
{
_filterCollection.Add(index, item);
}
}
}
EventsTracker.AddEvent(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
shouldRaiseEvents = true;
}
private void UpdateFilterInternal(OrderedListInternal <int, T> filterCollection, FilterDelegate <T> filter, NotificationType notificationType)
{
var currentFilter = filter;
filterCollection.Clear();
var items = GetItems();
if (currentFilter != null)
{
for (var index = 0; index < items.Count; index++)
{
var item = items[index];
if (currentFilter(item))
{
filterCollection.Add(index, item);
}
}
}
OnCollectionChanged(Empty.ResetEventArgs, notificationType);
}