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2026-09-23-zone-guard-target

title: A zone guard takes the navigation target as its second argument affects: dartway_core_flutter: "0.20.0-dev.3" dartway_router: "2.0.0"​

Who is affected​

Every project: each zone declares zoneGuards, and DwNavigationGuard now takes two arguments — the router state, as before, and the DwNavigationTarget being entered. A guard written with one parameter no longer compiles.

What to change​

In every *_navigation_zone.dart, give each guard the second parameter. Where the guard does not need it:

- (state) => state.isSignedIn ? null : AuthNavigationZone.auth.fullPath,
+ (state, _) => state.isSignedIn ? null : AuthNavigationZone.auth.fullPath,

What the parameter is for. The skeleton's gates now do this; to do the same, send a signed-out person to sign-in with where they were going, and send them on once signed in. <project>_flutter/lib/core/router/navigation_zones/auth_navigation_zone.dart:

List<DwNavigationGuard<AppRouterState>> get zoneGuards => [
  (state, target) => state.isSignedIn
      ? _returnTo(target) ?? AppNavigationZone.home.fullPath
      : null,
];

static String signInFrom(DwNavigationTarget target) => Uri(
  path: auth.fullPath,
  queryParameters: target.location == '/' ? null : {'from': target.location},
).toString();

static String? _returnTo(DwNavigationTarget target) {
  final from = target.uri.queryParameters['from'];
  final ownPath = from != null && from.startsWith('/') && !from.startsWith('//');
  return ownPath ? from : null;
}

and in the zones behind the gate:

- (state) => !state.isSignedIn ? AuthNavigationZone.auth.fullPath : null,
+ (state, target) =>
+     state.isSignedIn ? null : AuthNavigationZone.signInFrom(target),

A sign-in screen that navigates somewhere itself after signing in would override this; the skeleton's does not, and lets the guard decide.

How to check​

flutter analyze in the Flutter package: no list_element_type_not_assignable on zoneGuards.