Every Flutter developer has run into the Sticky State Dilemma.
You build a login screen. When authentication fails, your state container emits an error. You catch it in your UI and show a SnackBar. Everything works—until the user rotates their phone, pulls down the notification shade, or types on the virtual keyboard.
Suddenly, the widget tree rebuilds. The state container is still holding AuthErrorState("Invalid password"). The UI listener fires again. And a duplicate snackbar appears out of nowhere.
In this article, we’ll explore why domain state machines struggle with transient UI events, how the classic BLoC community worked around this with package:bloc_presentation, and how BlocSignal lets you handle one-shot side effects cleanly with zero additional package dependencies.
1. The Root Problem: Persistent State vs. Ephemeral Actions
