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;
}
}
private static void UpdateFilterItems(OrderedListInternal <int, T> filterCollection, int index, int value)
{
if (filterCollection.Count == 0)
{
return;
}
int start = filterCollection.IndexOfKey(index);
if (start == -1)
{
if (filterCollection.Keys[filterCollection.Count - 1] < index)
{
return;
}
for (int i = 0; i < filterCollection.Count; i++)
{
int key = filterCollection.Keys[i];
if (key < index)
{
continue;
}
filterCollection.Keys[i] = key + value;
}
return;
}
for (int i = start; i < filterCollection.Count; i++)
{
filterCollection.Keys[i] += value;
}
}
private void UpdateItem(NotifyCollectionChangedEventArgs e, out bool shouldRaiseEvents)
{
shouldRaiseEvents = false;
int filterIndex;
switch (e.Action)
{
case NotifyCollectionChangedAction.Add:
var item = (T)e.NewItems[0];
UpdateFilterItems(e.NewStartingIndex, 1);
if (!_filter(item))
{
return;
}
filterIndex = _filterCollection.Add(e.NewStartingIndex, item);
EventsTracker.AddEvent(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, item,
filterIndex));
shouldRaiseEvents = true;
break;
case NotifyCollectionChangedAction.Remove:
filterIndex = _filterCollection.IndexOfKey(e.OldStartingIndex);
UpdateFilterItems(e.OldStartingIndex, -1);
if (filterIndex == -1)
{
return;
}
_filterCollection.RemoveAt(filterIndex);
EventsTracker.AddEvent(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove,
e.OldItems[0], filterIndex));
shouldRaiseEvents = true;
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;
EventsTracker.AddEvent(
new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Replace,
e.NewItems[0], oldItem, filterIndex));
}
else
{
T oldValue = _filterCollection.GetValue(filterIndex);
_filterCollection.RemoveAt(filterIndex);
EventsTracker.AddEvent(new NotifyCollectionChangedEventArgs(
NotifyCollectionChangedAction.Remove, oldValue,
filterIndex));
}
shouldRaiseEvents = true;
break;
case NotifyCollectionChangedAction.Reset:
UpdateFilterInternal(out shouldRaiseEvents);
break;
default:
//For Move support.
if (e.Action.ToString("G") != "Move")
{
break;
}
var movedItem = (T)e.NewItems[0];
filterIndex = _filterCollection.IndexOfKey(e.OldStartingIndex);
UpdateFilterItems(e.OldStartingIndex, -1);
UpdateFilterItems(e.NewStartingIndex, 1);
if (filterIndex == -1 || !_filter(movedItem))
{
return;
}
_filterCollection.RemoveAt(filterIndex);
var newIndex = _filterCollection.Add(e.NewStartingIndex, movedItem);
EventsTracker.AddEvent(new NotifyCollectionChangedEventArgs(
NotifyCollectionChangedAction.Remove, e.OldItems[0],
filterIndex));
EventsTracker.AddEvent(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add,
movedItem,
newIndex));
shouldRaiseEvents = true;
break;
}
}