Change design options with slider

[Thomas_Corrie]

The Revit API doesn’t allow you to set the design option for an element programmatically. There are some workarounds suggested in this thread:

How to set Element's Design Option?

Is it possible to set an element’s Design Option? I’ve got a graph that creates 3D Masses from Rooms, but now we’ve got a project with some of the Rooms in Design Options, so I need to set my Masses to match. I tried the Element.GetParameterValueByName on the Rooms and then Element.SetParameterByName on the Mass, but I get a “The parameter is read-only” error on the Set.