How to disable toggling with flex buttonbar

How to disable the toggle nature of buttons in spark:Buttonbar so that it would behave similar to mx:ButtonBar开发者_C百科?

---

This works on the button bar:

requireSelection="false"

---

If you only want to make a visual change:

Create a custom skin class so that the "down state" of the button uses the same skin as the 'up state'.