Public Transit Calculate Route

_{Last updated: April 7, 2026 | 2 minutes read}

UIKit

This example demonstrates how to use GEMKit in a UIKit application to calculate a public transit route between two locations and render it on the map with a route summary.

Check the full implementation on GitHub.

Public Transit Calculated Routes

UI and Map Integration

The view controller is minimal — a map view and a NavigationContext configured for public transit:

ViewController.swiftView on GitHub

class ViewController: UIViewController, UISearchBarDelegate {

    var mapViewController: MapViewController?
    var navigationContext: NavigationContext?
    var trafficContext: TrafficContext?

    override func viewDidLoad() {
        super.viewDidLoad()

        self.title = "Public Transit"
        self.navigationItem.largeTitleDisplayMode = .never

        self.createMapView()
        self.mapViewController!.startRender()
        self.addRouteButton()
    }

Calculating the Public Transit Route

Setting setTransportMode(.public) on the preferences switches the engine to the public transit planner. The result is presented on the map with a route summary:

info

For a public transport route the maximum number of waypoints is 2.

ViewController.swiftView on GitHub

    @objc func routeButtonAction(item: UIBarButtonItem) {

        if self.navigationContext == nil {

            let preferences = RoutePreferencesObject.init()
            preferences.setTransportMode(.public)
            preferences.setRouteType(.fastest)

            self.navigationContext = NavigationContext.init(preferences: preferences)
        }

        if self.trafficContext == nil {

            self.trafficContext = TrafficContext.init()
            self.trafficContext?.setUseTraffic(.useOnline)
        }

        let waypoints = [

            LandmarkObject.landmark(
                withName: "San Francisco", location: CoordinatesObject.coordinates(withLatitude: 37.77903, longitude: -122.41991)),
            LandmarkObject.landmark(
                withName: "San Jose", location: CoordinatesObject.coordinates(withLatitude: 37.33619, longitude: -121.89058))
        ]

        item.isEnabled = false

        self.navigationContext?
            .calculateRoute(
                withWaypoints: waypoints,
                completionHandler: { [weak self] (results: [RouteObject]) in

                    guard let strongSelf = self else { return }

                    if !results.isEmpty {

                        strongSelf.mapViewController?
                            .presentRoutes(results, withTraffic: strongSelf.trafficContext, showSummary: true, animationDuration: 1000)
                    }

                    item.isEnabled = true
                })
    }