title: Scroll a ListBox's VirtualizingStackPanel with buttons
body: <p>I have a Listbox displaying 5 items at a time, horizontally.  I want to implement a 'Previous' and 'Next' button that when clicked, will display the previous set of 5, or next set of 5 items.  I am not displaying the horizontal scroll bar, as I don't want a user to navigate with that.</p>
  
  <p>Is there already some functionality implemented so I can do this, or do I need to write code to calculate what items I'm displaying, etc, in the button's click events?</p>
  
  <p>Thanks in advance!</p>