Directions Rendering

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When getting the result Route from a Directions Service, we may want to display this Route on a map. To perform this task the MPDirectionsRenderer can be used.

This example shows how to setup a query for a route and display the result on a Google Map using the MPDirectionsRenderer:

let directions = MPDirectionsService.init()
let renderer = MPDirectionsRenderer.init()
renderer.fitBounds = true
renderer.delegate = self

let origin = MPPoint.init(lat: 57.057917, lon: 9.950361, zValue:0)
let destination = MPPoint.init(lat: 57.058038, lon: 9.950509, zValue:0)

let directionsQuery = MPDirectionsQuery.init(originPoint: origin!, destination: destination!)

directions.routing(with: directionsQuery) { (route, error) in
renderer.map = self.map
renderer.route = route
renderer.routeLegIndex = 0
renderer.animate(5)
}

Controlling the Visible Segments on the Directions Renderer

As previously mentioned, the route object is seperated into objects of MPRouteLeg and these legs are again seperated indo objects of MPRouteStep. Unless the Route only contains one Leg, the Directions Renderer does not allow the full Route to be rendered all at once. A specific segment of the route can be rendered by setting the routeLegIndex and/or routeStepIndex properties on the MPDirectionsRenderer.

let renderer = MPDirectionsRenderer.init()
renderer.routeLegIndex = 0
renderer.routeStepIndex = 1

The length of the legs and steps arrays determines the possible values of routeLegIndex and routeStepIndex (0 ..< length).

Reacting to Directions Renderer Events

Assigning a MPDirectionsRenderer delegate will make it possible to know which floor the currently rendered part of the route belongs to. As such, you may want to change the currently visible floor on MPMapControl like shown in the example below.

func floorDidChange(_ floor: NSNumber!) {
mapControl?.currentFloor = floor
}

Reacting to Label Tapping

The Directions Labels refer to labels shown at the start and/or end of the rendered route segment (leg or step) path, that may provide contextual information or show instructions for the needed user action at that point. E.g. the end label can be retrieved with .nextRouteLegButton. The labels are created as simple UIButton instances that are rendered as markers on the map. As with most buttons, it is possible to add targets to these labels, so you can react to touch events.


override func viewDidAppear(_ animated: Bool) {
let renderer = MPDirectionsRenderer.init()
renderer.delegate = self
renderer.map = self.map

renderer.nextRouteLegButton?.addTarget(self, action: #selector(nextLeg), for: .touchUpInside)
renderer.previousRouteLegButton?.addTarget(self, action: #selector(previousLeg), for: .touchUpInside)
}

@objc func nextLeg() {
renderer.routeLegIndex += 1
}

@objc func previousLeg() {
renderer.routeLegIndex -= 1
}

In the above example, a target is added to nextRouteLegButton and nextRouteLegButton calling the method nextLeg and previousLeg respectively. These methods then changes the visible Route Leg.