Due to the virtualization in RadPageView visual items are being only created when needed and reused later on. In order to properly be able to mark certain items, you could use the Tag property of the data items:
Depending on where you are setting the tag, the way to set it would vary. For example, here is how to set it when creating an item:
Dim dataItem As New ListViewDataItem()
dataItem.Tag = 2
I hope this helps.
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