Session class

The Session Facade.

Provides a Laravel-style flash-data API for surviving navigation: flash input on failed submit, navigate back, repopulate the form with Session.old / Session.error.

// On failed submit:
Session.flash(form.data);
Session.flashErrors({'email': ['Invalid email.']});
MagicRoute.back();

// In the form view:
WFormInput(
  initialValue: Session.old('email') ?? '',
);
if (Session.hasError('email'))
  WText(Session.error('email')!, className: 'text-red-500');

Flash data survives exactly one navigation. Call Session.tick on every real route change. The router delegate listener can fire for non-navigation events (redirect re-evaluation, notifier rebuilds), so gate the tick on an actual location change:

var lastLocation = MagicRouter.instance.currentLocation;
MagicRouter.instance.routerConfig.routerDelegate.addListener(() {
  final currentLocation = MagicRouter.instance.currentLocation;
  if (currentLocation == lastLocation) return;
  lastLocation = currentLocation;
  Session.tick();
});