filter method
Set filter conditions for the subscription with type safety
Example
realtime.observe<Map<String, dynamic>>('messages.chat')
..filter(RealtimeEqFilter('room_id', 'room123'))
..on(RealtimeObserverEvent.data, (event) {
print('Message in room123: ${event.data}');
});
Implementation
RealtimeObserver<T> filter(RealtimeFilter filter) {
_filter = filter;
return this;
}