I am trying to apply the below code on the Button DisplayMode, But getting error of Enum
If(And(CountRows(GalleryCartOrder.AllItems)>=1,Sum(GalleryCartOrder.AllItems, Value(LineTotalAmt.Text)) > 0),
DisplayMode=DisplayMode.Edit,
DisplayMode=DisplayMode.Disabled)

Please advise what correction can be done to get the result as required.