Scala JavaFX application

I am wrapping a TextBox in a ScrollPane and also a Text in a ScrollPane.
I put ScrollBarPolicy.AS_NEEDED
and I did not see the scrollbars appear if the contained component expanded in the size.

It might be way I am use the component thought. I thought LayoutInfo.HGROW and LayoutInfo.VGROW allowed the child of the ScrollPane to resize if required.

Hmm