subscription

Returns a Subscription that can be used to subscribe to this channel group.

Channel group subscriptions support passing com.pubnub.api.v2.subscriptions.SubscriptionOptions.receivePresenceEvents in options to enable receiving presence events.

com.pubnub.api.v2.subscriptions.SubscriptionOptions.filter can be used to filter events delivered to the subscription.

For example, to create a subscription that only listens to presence events:

channelGroup.subscription(SubscriptionOptions.receivePresenceEvents() + SubscriptionOptions.filter { it is PNPresenceEventResult } )

Warning: if a channel is part of more than one channel group, and you create subscription to both (or more) those groups using a single com.pubnub.api.PubNub instance, you will only receive events for that channel in one channel group subscription.

For example, let's say "channel_1" is part of groups "cg_1" and "cg_2". If you only subscribe to "cg_1", or you only subscribe to "cg_2", you will get all events for "channel_1". However, if in your app you subscribe to both "cg_1" and "cg_2" at the same time, you will only receive events for "channel_1" in one of those subscriptions, chosen at random.

This limitation is due to how the server manages channels and channel groups.

Parameters