created a custom measure for planner code but unable to use it as filter

Summary: My client want to use filtering by planner code. I defined planner code as a custom measure. However, It does not showup as a filterable measure. How can I make it filterable?

Content (please ensure you mask any confidential information): I tried using the planner as a segment approach. But that is not acceptable as it hinders dynamic linking with other tables. Planner code as an attribute approach works for using dynamic links, but is not filterable. I am stuck. Any ideas as to how to make a planner code as a custom attribute show up as a filterable attribute?