internal void RaiseCollectionPathChanged(CollectionPathChangedEventArgs e) => CollectionChanged?.Invoke(this, e);
private void OnTrackerCollectionChanged(object sender, CollectionPathChangedEventArgs e)
{
e.PropertyPath = ConstructPropertyPathForParent(e.PropertyPath);
_parentTracker.RaiseCollectionPathChanged(e);
}
private void OnCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
switch (e.Action)
{
case NotifyCollectionChangedAction.Reset:
while (_itemTrackers.Any())
{
RemoveTrackerAt(0);
}
Tracker.RaiseCollectionPathChanged(CollectionPathChangedEventArgs.CreateResetArgs());
break;
case NotifyCollectionChangedAction.Add:
var index = (e.NewStartingIndex == -1) ? _itemTrackers.Count : e.NewStartingIndex;
foreach (var item in e.NewItems)
{
InsertTrackerAt(index++, item);
}
Tracker.RaiseCollectionPathChanged(new CollectionPathChangedEventArgs(CollectionPathChangedAction.Add, e.NewItems, e.NewStartingIndex));
break;
case NotifyCollectionChangedAction.Remove:
foreach (var item in e.OldItems)
{
RemoveTrackerOf(item);
}
Tracker.RaiseCollectionPathChanged(new CollectionPathChangedEventArgs(CollectionPathChangedAction.Remove, e.OldItems, e.OldStartingIndex));
break;
case NotifyCollectionChangedAction.Replace:
// Remove old items...
foreach (var item in e.OldItems)
{
RemoveTrackerOf(item);
}
Tracker.RaiseCollectionPathChanged(new CollectionPathChangedEventArgs(CollectionPathChangedAction.Remove, e.OldItems, e.OldStartingIndex));
// ...and insert replacement items
var i = (e.NewStartingIndex == -1) ? _itemTrackers.Count : e.NewStartingIndex;
foreach (var item in e.NewItems)
{
InsertTrackerAt(i++, item);
}
Tracker.RaiseCollectionPathChanged(new CollectionPathChangedEventArgs(CollectionPathChangedAction.Add, e.NewItems, e.NewStartingIndex));
break;
case NotifyCollectionChangedAction.Move:
// Remove items at old indices...
foreach (var item in e.OldItems)
{
RemoveTrackerOf(item);
}
Tracker.RaiseCollectionPathChanged(new CollectionPathChangedEventArgs(CollectionPathChangedAction.Remove, e.OldItems, e.OldStartingIndex));
// ...and re-insert them at the new indices
var i2 = e.NewStartingIndex;
foreach (var item in e.NewItems)
{
InsertTrackerAt(i2++, item);
}
Tracker.RaiseCollectionPathChanged(new CollectionPathChangedEventArgs(CollectionPathChangedAction.Add, e.NewItems, e.NewStartingIndex));
break;
}
}
