'ngsolve.comp.SumOfIntegrals' object has no attribute 'SetDefinedOnElements'

The attached file come from this diccusion with a small change.

The part that I changed is:

interfacebfi = SymbolicBFI (cf1+cf2+cf3, VOL, skeleton=True ) interfacebfi.SetDefinedOnElements(interface_indicator) a += interfacebfi

In many example on the forum, a+=something*dx is used to define a bilinear form for a weak formulation instead of using SymbolicBFI. I think they are interchangeable, so I guessed the above code can be rewrite as in the following one.

interfacebfi = (cf1+cf2+cf3)*dx(skeleton=True ) interfacebfi.SetDefinedOnElements(interface_indicator) a += interfacebfi

Then, there is an error when I run the file.

AttributeError: 'ngsolve.comp.SumOfIntegrals' object has no attribute 'SetDefinedOnElements'

I’m just wondering if there is any way to code in the second way, which is equivalent to the first one such that the original code works.
Many thanks in advanced.

Attachment: 2domain_2020-05-27.py

you are right, this was missing.
It is added in the current master and nightly and next release builds.
There you can use

... * dx(definedonelements=bitarray)