isEmpty property
Whether this stream contains any elements.
Waits for the first element of this stream, then completes the returned
future with false
.
If this stream ends without emitting any elements, the returned future is
completed with true
.
If the first event is an error, the returned future is completed with that error.
This operation listens to this stream, and a non-broadcast stream cannot be reused after checking whether it is empty.
Implementation
@override
Future<bool> get isEmpty => controller.stream.isEmpty;