Binding aggregate to list doesn't work?

I want to bind an aggregate (a filter, actually) to a list. The filter should filter so that it only show the rows of the currently logged in user. However, when I drag-and-drop an aggregated table to an app, and I deploy it, it's always empty. Non-aggregated tables work, but aggregated ones always return zero. Why can't I bind an aggregated table to a list?

Are you filtering by username or by user id? For the username, the filter in your aggregate should look something like this:

TestEntity.Username = GetUser(GetUserId()).User.Username

For user id, it would be something like this:

TestEntity.UserId = GetUserId()