WPF: List boxes and virtualization

Question

1. How do I know whether or not my list is being virtualized?

2. How do I make this snippet virtualized?

Answer 1

To know if it is virtualized you can simply add 10K dummy entries to the collection and see how fast the loading happens as well as how fast the vertical scroll works which will clearly tell a big difference. I guess you need to change your StackPanel in the control template to VirtualizingStackPanel.