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2026-09-30-router-state-provider

title: The router follows a provider; AppRouterState is a record, not a ChangeNotifier affects: dartway_core_flutter: "0.21.0-dev.17" dartway_router: "3.0.0" dartway_studio_binding: "0.2.1"​

Who is affected​

Every project: DwAppRouter takes the ref of the provider that builds it, and routerState is a provider of the value the guards decide by, no longer a Listenable. The router listens to it, re-runs its guards whenever the value changes and disposes itself with its provider. The AppRouterState extends ChangeNotifier every project holds — with its // dw:allow-stateful marker — no longer fits DwAppRouter, and flutter analyze fails on the router file.

What to change​

<project>_flutter/lib/core/router/app_router_state.dart — the class becomes a record and the provider that derives it. The listens it made become watches; the fields become the record's:

- // dw:allow-stateful DwAppRouter re-runs its guards on a Listenable …
- class AppRouterState extends ChangeNotifier {
-   AppRouterState(Ref ref) {
-     ref.listen<int?>(dw.accountId, (_, accountId) { … notifyListeners(); }, …);
-     ref.listen<UserRole?>(myProfileProvider.select(…), (_, next) { … }, …);
-   }
-   bool isSignedIn = false;
-   UserRole? role;
- }
+ typedef AppRouterState = ({bool isSignedIn, UserRole? role});
+
+ final appRouterStateProvider = Provider<AppRouterState>(
+   (ref) => (
+     isSignedIn: ref.watch(dw.accountId) != null,
+     role: ref.watch(myProfileProvider.select((profile) => profile.value?.role)),
+   ),
+ );

A project whose state carries more than these two fields gives the record the same fields, each watched from the provider it used to listen to. Keep it immutable and with value equality — a record, or a class with == — since an equal value re-runs nothing. Drop the package:flutter/foundation.dart import if nothing else uses it.

<project>_flutter/lib/core/router/router.dart — delete the old appRouterStateProvider (it moved into the file above), and build the router with ref and the provider itself:

- final appRouterStateProvider = Provider<AppRouterState>((ref) {
-   final state = AppRouterState(ref);
-   ref.onDispose(state.dispose);
-   return state;
- });
-
  final appRouterProvider = Provider<DwAppRouter<AppRouterState>>((ref) {
-   final routerState = ref.watch(appRouterStateProvider);
    final router = DwAppRouter<AppRouterState>(
-     routerState: routerState,
+     ref: ref,
+     routerState: appRouterStateProvider,
      …
    );
    …
-   ref.onDispose(router.router.dispose);
    return router;
  });

The ref.onDispose(router.router.dispose) line has to go: the router disposes itself now, and a second dispose fails in debug — dartway check fails it as routerDisposedByApp. The zone files and their guards (state.isSignedIn, state.role) do not change.

Keep MaterialApp.router(routerConfig: ref.watch(appRouterProvider).router) a watch: Riverpod pauses a provider nobody listens to, and the router stops following its state with it.

A project with DwStudioBinding passes router: as before.

How to check​

flutter analyze in the Flutter package is clean; grep -rn "router\.dispose" lib/ finds nothing (dart run dartway_cli:dartway check fails a leftover as routerDisposedByApp); the check prints no 🔓 Allowed by dw:allow-stateful for AppRouterState; signing out of the running app returns to the sign-in screen, and a link into the app opened signed out ends there after signing in.