TAdvStringGrid how to refresh virtual cells

Hi, I've implemented the OnGetDisplText in a TAdvStringGrid to use the "virtual cell" feature, but how do you tell the grid to update the currently viewed cells if some other process changes the data?  I've tried Refresh, Invalidate, Repaint, RepaintCol, RepaintCell, nothing seems to work.  Do I just have to clear the grid and reload it?  Ideally I want to keep the top row and selection and just refresh the currently viewed values because I know the number of items hasn't change. Thx.

Normally Invalidate or Repaint* methods should do this.

Did you try to reproduce this in a simple new test app?
Doh, as soon as I saw your comment I realised I wasn't reloading the new data from the DB.  My bad, must have been working too late last night.
Thanks anyway, always appreciate the swift response.