presenceChannel method
Get a presence channel instance by name.
Implementation
@override
PusherPresenceChannel presenceChannel(String name) {
if (channels['presence-$name'] == null) {
channels['presence-$name'] = PusherPresenceChannel(
pusher,
'presence-$name',
options,
);
}
return channels['presence-$name'] as PusherPresenceChannel;
}