StreamBuilder. Bad state: Stream has already been listened to

Use the rx_dart library from pubspec: https://pub.dartlang.org/packages/rxdart

Now change your Stream<Something> declaration to be a BehaviorSubject<Something>. (The BehaviorSubject is a kind of stream that has memory of the last value transmited. There is other subjects available on the library like the PublishSubject and the ReplaySubject, check their docs for your use case).

The rx_dart library is an extension of the Stream base classes and are much more powerful and easier to work.

Check their GitHub: https://github.com/ReactiveX/rxdart

So, all I've needed to do is replace

final StreamController<bool> streamController = StreamController<bool>();

with final StreamController<bool> streamController = StreamController<bool>.broadcast();