Filtering by the top level view in a hierarchical list
I make extensive use of the hierarchical list function, but there is one thing I can't work out how to do. I've made a minimal example here:
I have three tables, projects, groups and records. Projects can have several groups, and groups contain several records. I would like to be able to filter the view based on which project a group is assigned to. I can add a lookup field inside the record (which is what is shown in my screenshot filtering for project Bob), but I would like to have groups A, B and C hidden in this view, because they are on project Alice.
I can't use the 'hide sections with no additional rows' option, because I would like my users to be able to add new records to group F, which is a member of project Bob but empty.
Are there any features which would allow me to achieve this goal?
