UI vs Logic
Widgets render. Notifiers decide. Where to put each thing.
Kit rule: widgets render and capture input. They never contain business logic.
What goes where
| Widget (UI) | Notifier (logic) |
|---|---|
Text(...), KasyButton(...) | goRouterProvider.go('/') |
FocusScope.of(context).unfocus() | toastProvider.success(...) |
context.pop() in a modal | Redirecting after login, purchase, error |
Providers in the notifiers
ref.read(goRouterProvider).go('/route');
ref.read(toastProvider).error(title: '...', text: '...');
final t = ref.read(translationsProvider);Why it matters
- Tests live in the notifier, not in the UI
- The same screen works on web and native
- AI and new devs know where to look
Last updated on 08/02/2026