onPresent property
final
A callback that add a new Route to the provided navigator.
The callback must use one of the API methods on the NavigatorState that have "restorable" in their name (e.g. NavigatorState.restorablePush, NavigatorState.restorablePushNamed, etc.) and return the opaque ID returned by those methods.
This callback is invoked when present is called with the arguments
Object that was passed to that method and the NavigatorState obtained
from navigatorFinder.
Implementation
final RoutePresentationCallback onPresent;