onLevelChanged property
Returns a stream of level values set to this Logger.
You can listen for set levels using the standard stream APIs, for instance:
logger.onLevelChanged.listen((level) { ... });
A state error will be thrown if the level is changed inside the callback.
Implementation
Stream<Level?> get onLevelChanged {
_levelChangedController ??= StreamController<Level?>.broadcast(sync: true);
return _levelChangedController!.stream;
}