I'm using the Ultimate ListBox for WPF with a custom AsyncDataSourceProvider class. My data has a simple two-level grouping.

When I scroll to the bottom of the list and try to select the last item, it is selected for a second, but then changes to select the previous item. I end up having to click on the item three times before the selection sticks.

I do have a handler on the SelectionChanged event, but this simply checks the SelectedRanges.Count property, and then calls BeginGetSelectedItems to find the selected item. IMO, this shouldn't cause the selection to change.

Can anyone suggest where I might be going wrong?

Hi Richard, 

Could you send us a sample application that demonstrates this so that we investigate it in more detail?

You can send it to support@xceed.com. Please include a reference to this forum post in you email.  

OK, I've sent a reproduction.

It's not consistent: sometimes the selection works first time; other times, it takes several clicks.

Also, the last item is sometimes not displayed fully, even though the list won't let me scroll down any further.

Sharing the answer from support to the community: 

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