>I thought of that too. Maybe a dum question , but how does this work?

Ok, here's another fantastic trick. :)

In this example, Recherche is the object name of a grid. Whenever the user changes the order of the grid alias, we reset all the grid header backcolor property to the default and put the actual field order to a different color. aOrdre array contains a list of all the field names in the grid and tnBar is the actual parameter we pass to this method to know which one to highlight.

ThisForm.Recherche.SetAll('BackColor',RGB(192,192,192),'Header')
FOR lnCompteur=1 TO ThisForm.Recherche.ColumnCount
   IF ThisForm.Recherche.Columns(lnCompteur).ControlSource==;
     ThisForm.Recherche.RecordSource+'.'+ALLTRIM(ThisForm.aOrdre[tnBar,3])
   ThisForm.Recherche.Columns(lnCompteur).Header1.BackColor=RGB(255,255,0)
   ENDIF
NEXT