IronPython error - 'NoneType' object has no attribute 'ActiveUIDocument'

[jstro]

I have been working with this code all week (only snip included) and then it just stopped working.

[SeanP]

Does not contain a definition for 'Application'

this refers to your class not the Revit API Document class, and you haven’t declared a property called Application which is why you are seeing that exception. Even if you did have the active document object, the Autodesk.Revit.ApplicationServices.Application which is returned does not contain a property called ActiveUIDocument (its found in Autodesk.Revit.UI.UIApplication) so it will still throw an exception. Instead, get the active document object (I think the macro template which Revit genera…