Forcing Expressions in a Datawindow

PB 11.5.2

Greeting All,

My understanding is that all datawindow expressions run, calculate, etc.. when each row is retrieved.

I have a user-defined function() in a tooltip expression that returns the time left from one datetime to another.

My desire is that each time a user hovers over the object within the datawindow, the Tooltip expression is re-run.

Is there a way to tell a datawindow row to re-run the expressions within that row, or even specifically against a particular expression (tooltip!)

Thanks!

Jason Lipman