didChangeTop method

  1. @override
void didChangeTop(
  1. Route topRoute,
  2. Route? previousTopRoute
)
override

The top most route has changed.

The topRoute is the new top most route. This can be a new route pushed on top of the screen, or an existing route that becomes the new top-most route because the previous top-most route has been popped.

The previousTopRoute was the top most route before the change. This can be a route that was popped off the screen, or a route that will be covered by the topRoute. This can also be null if this is the first build.

Implementation

@override
void didChangeTop(Route<dynamic> topRoute, Route<dynamic>? previousTopRoute) {
  final cached = _namedPages[topRoute.settings.name];
  if (cached != null) {
    final properties = updateProperties(topRoute, previousTopRoute);
    cached.start(propertyUpdates: properties);
    return;
  }

  final name = namePage(topRoute);
  final properties = initialProperties(topRoute, previousTopRoute);
  final page = FS.page(name, properties: properties);
  _namedPages[name] = page;
  page.start();
}