Android Question Simple Scrollable Label / Text Field

What is the best way to create and update a label / text field which will be scrollable when its contents are larger than the screen? Can you point me at some example code.

I've tried the CustomListView and while I can successfully add a single item which scrolls nicely I can't work out how to replace the existing text with new text. Given that this is such a fundamental requirement I'm sure that the answer is simple but I can't fathom it.