RestorableRouteFuture<T> class

Gives access to a Route object and its return value that was added to a navigator via one of its "restorable" API methods.

When a State object wants access to the return value of a Route object it has pushed onto the Navigator, a RestorableRouteFuture ensures that it will also have access to that value after state restoration.

To show a new route on the navigator defined by the navigatorFinder, call present, which will invoke the onPresent callback. The onPresent callback must add a new route to the navigator provided to it using one of the "restorable" API methods. When the newly added route completes, the onComplete callback executes. It is given the return value of the route, which may be null.

While the route added via present is shown on the navigator, it can be accessed via the route getter.

If the property is restored to a state in which present had been called on it, but the route has not completed yet, the RestorableRouteFuture will obtain the restored route object from the navigator again and call onComplete once it completes.

The RestorableRouteFuture can only keep track of one active route. When present has been called to add a route, it may only be called again after the previously added route has completed.