The isActive condition of the TopicGroup is effectively AND'ed with any other conditions on the nested TopicEntry's. In other words, a TopicEntry within the TopicGroup is active if the TopicEntry would otherwise be acive AND the TopicGroup is active.
TopicEntry objects are associated with the group via the 'location' property - set the location of the TopicEntry to point to the containing TopicGroup.
You can put a TopicGroup anywhere a TopicEntry could go - directly inside an Actor, inside an ActorState, or within another TopicGroup. The topic entries within a topic group act as though they were directly in the topic group's container.
TopicGroup : object