subscribe
Subscribes to Content Cards events. The subscriber callback will be called when Content Cards is updated. The subscriber will be called with a ContentCardsUpdatedEvent.
Subscriptions should be cleaned up manually by calling IBraze.removeSingleSubscription.
All events are triggered from background threads and isolate any encountered exceptions. If you need to do work on the UI thread in response to an event, you will need to coordinate that in the IEventSubscriber's trigger method.
Parameters
subscriber
A callback that will be executed when Content Cards are updated.