fun registerRoutesObserver(routesObserver: RoutesObserver)

Registers RoutesObserver. The updates are available when a new list of routes is set. The route at index 0, if exist, will be treated as the primary route for 'Active Guidance'.

If the observer is registered when new routes are being set with MapboxNavigation.setNavigationRoutes, the observer waits for the processing to finish before delivering the latest result.