I have a text field as an item on one of my pages. Let's call it 'P11_Manager', without the quotes of course. I would like to have a button that takes the value in that field and does <action>. I have already done that. However, some Employees don't have a Manager, so I would like the button to ONLY appear if the Manager field is occupied. In other words, if Manager != null, show button; or if Manager == null, hide Button. How would I do that?