Guards & redirects

Guards and redirects are control flow on the route itself — mix them into a route class.

RouteGuard — veto a pop

RouteGuard lets a screen refuse to be popped (e.g. unsaved changes). canPop is a synchronous getter — predictive back needs a sync answer — and raku_router wraps the guarded screen in a PopScope, so it is honoured by every back path: the predictive-back gesture, an imperative Navigator.pop, the system back button, and context.pop().

class Editor extends AppRoute with RouteGuard {
  const Editor();
  @override
  bool get canPop => !hasUnsavedChanges; // false blocks the pop

  @override
  Listenable? get rebuildOn => formState; // re-evaluate canPop as state changes

  @override
  void onPopBlocked(BuildContext context) {
    // Confirm here — e.g. show a "discard changes?" dialog.
  }
}

onPopBlocked fires on every blocked back path, including the discrete system back button in Router mode.

RouteRedirect — resolve before showing

Return a different route to redirect, or null/the same destination to stay. Redirect chains are followed and loop-protected by the package — you don’t hand-write the “am I already going there?” check. Redirects resolve on push and when reached via a deep link.

class LegacyNote extends AppRoute with RouteRedirect {
  const LegacyNote(this.id);
  final String id;
  @override
  RakuRoute redirect() => NoteDetail(id); // resolved before it's shown
}