ErrorHandlingMixin

mixin ErrorHandlingMixin<Page extends BasePage> on BaseState<Page> {
  @override
  void initState() {
    super.initState();
    widget.bloc.errorStream
			// this will preven multiple messages from showing up in a short interval of time
        .transform(new ThrottleStreamTransformer((_) => TimerStream(true, const Duration(seconds: 2))))
        .listen((error) => showErrorSnackbar(error, scaffoldKey.currentState));
  }

  void showErrorSnackbar(String event, ScaffoldState context) {
    if (event != null) {
      context.showSnackBar(new SnackBar(
        content: new Text(event),
      ));
    }
  }
}