Modifying an item in a WPF sorted ListView doesn't change the sort position of that item.

Question

I have a sortable listview that gets filled with a live data as it comes. Sorting works perfectly but the real problem arises when an item is modified after being added to the collection. The position of modified item does not change no matter what the sort orders is.

I have googled it but couldn't find a better solution to make my listview a perfect sorted listview.

Solutions??

Answer 1

I assume you are following an approach similar to this MSDN sample. If so, then sorting happens based on the collection view's SortDescriptions. As long as the source collection is observable, the sort order should be respected when items are added or removed from the collection.

The real problem arises when an item is modified after being added to the collection. In that case, the collection is not automatically re-sorted.

I explain the issue in detail in 'E' is for Editable Collection (in my ItemsControl A to Z series). I also present a few workarounds that offer different levels of performance. The most drastic is to force a re-sort of the entire collection by calling Refresh() on the CollectionView. If possible, I would avoid that and use a better option, like implementing IEditableObject on your items and issuing an Edit() followed by Commit() whenever the properties change on an item.