Navigation information

Track the user's progress along an itinerary.

Overview

WemapCoreSDK/NavigationInfo contains everything about the user's progress along an itinerary — current leg and step, distances and times, previous/next steps, and more. WemapCoreSDK/NavigationInfoHandler produces an updated WemapCoreSDK/NavigationInfo on request.

Navigation information depends on WemapCoreSDK/SessionConfig/userLocationProjectionOnItineraryEnabled:

• Enabled — the origin and user-projection distances are not included in the total, since those parts aren't visible to the user.
• Disabled — they are included (so the total itinerary distance won't equal distance-travelled + distance-remaining).

WemapCoreSDK

Compute an itinerary with session.itineraryProvider, hand it to session.navigationInfoHandler, then request info for a user position. WemapCoreSDK/NavigationInfoHandler holds its itinerary weakly, so keep a strong reference to the itinerary you assign:

final class ViewController: UIViewController {

    private var session: CoreSession!
    private var itinerary: Itinerary?      // retained; the handler holds it weakly

    private func computeItinerary() async throws {
        let origin = Coordinate(coordinate2D: .init(latitude: 43.610628, longitude: 3.876654))
        let destination = Coordinate(coordinate2D: .init(latitude: 43.609011, longitude: 3.917091))

        let itineraries = try await session.itineraryProvider.itineraries(
            origin: origin, destination: destination, travelMode: .bike(preference: .safest)
        )
        setItinerary(itineraries.first!)
    }

    private func setItinerary(_ itinerary: Itinerary) {
        self.itinerary = itinerary
        session.navigationInfoHandler.itinerary = itinerary

        let userPosition = Coordinate(coordinate2D: .init(latitude: 43.610107, longitude: 3.891805))
        let info = session.navigationInfoHandler.getNavigationInfo(userPosition: userPosition)
        print("navigation info: \(String(describing: info))")
    }
}

WemapMapSDK

WemapMapSDK/MapNavigationManaging (via mapView.navigationManager) observes the user's progress and emits an updated WemapCoreSDK/NavigationInfo on its navigationInfoUpdates stream. Set the cadence with navigationInfoUpdatesInterval:

final class NavigationInfoViewController: UIViewController {

    private var mapView: MapView!
    private var observationTasks: [Task<Void, Never>] = []

    func setUp() async throws {
        let session = try await MapSession(mapID: 19158, token: "YOUR_TOKEN")
        mapView = MapView(frame: view.bounds, session: session)
        mapView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
        view.addSubview(mapView)

        _ = try await mapView.awaitLoaded()
        observeNavigationInfo(mapView)
    }

    private func observeNavigationInfo(_ mapView: MapView) {
        mapView.navigationManager.navigationInfoUpdatesInterval = .seconds(2)   // default is .seconds(1)
        mapView.userTrackingMode = .follow

        let updates = mapView.navigationManager.navigationInfoUpdates
        observationTasks = [
            Task { [weak self] in
                for await info in updates {
                    guard self != nil else {
                        return
                    }
                    print("Navigation info updated: \(info)")
                }
            }
        ]

        Task { try await startNavigation() }
    }

    private func startNavigation() async throws {
        let origin = Coordinate(coordinate2D: .init(latitude: 43.610628, longitude: 3.876654))
        let destination = Coordinate(coordinate2D: .init(latitude: 43.609011, longitude: 3.917091))
        _ = try await mapView.navigationManager.startNavigation(origin: origin, destination: destination)
    }
}