listen method
- @protected
- @nonVirtual
Starts message receiving.
Registers message sink in MessageSinkRegister.
If this Listener's message sink is already registered, it's automatically unregistered first.
Implementation
@protected
@nonVirtual
void listen() {
if (_id != null) {
cancel();
}
_messageStreamController = StreamController<Message>();
_id = MessageSinkRegister()._add(
_messageStreamController!.sink,
onInitialMessage: onInitialMessage,
);
_messageSubscription = _messageStreamController!.stream.listen(onMessage);
}