C# Force ListBox to update elements

Question

I'm subclassing the standard ListBox control. I get notified of changes to any of the elements added to the list. The task is to update the text shown by the ListBox for the changing element.

I'm aware that i could just remove the changed element and add it again, but this seems not preferable for obvious reasons.

Answer 1

Unfortunately, the data-binding in ListView doesn't support regular (item) change notification events (FooChanged / INotifyPropertyChanged). However, if you know about the change, you can get the list to re-bind itself. Since you are subclassing, you can call:

this.RefreshItems();

or for a single item:

this.RefreshItem(index);

Otherwise, since this isn't public, you can simulate it by changing the DisplayMember:

lb.DisplayMember = "";
lb.DisplayMember = "Bar";

A little hacky, maybe, but it works, and maintains the current selection etc (unlike clearing the DataSource).

Answer 2

Why don't you manually update Text of an item in question? You might also consider rolling out your own databinding mechanism for ListBox. And check out ObjectListView to see if it's of any help.