Listbox InvalidateCell(-1,-1)

Does anybody know if this redraws every row in a listbox even if it is not visible or only the currently visible rows?

it only “invalidates” them. They are only “drawn” if they scroll into the visible view

this applies to any visible object… if it is not within the portal (form/window etc) visible to the user, it is not drawn until such time as it becomes so, this applies to objects with windows covering them etc.

Ahh … so it basically marks them as dirty but doesn’t update unless they are in view. Thank you.