Directions Rendering for Android

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When getting the resulting Route from a Directions Service, you 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:

void getRoute() {
MPDirectionsService directionsService = new MPDirectionsService(this);
MPDirectionsRenderer directionsRenderer = new MPDirectionsRenderer(mMapControl);

MPPoint origin = new MPPoint(57.057917, 9.950361, 0.0);
MPPoint destination = new MPPoint(57.058038, 9.950509, 0.0);

directionsService.setRouteResultListener((route, error) -> {
if (route != null) {
directionsRenderer.setRoute(route);
}
});

directionsService.query(origin, destination);
}
fun getRoute() {
val directionsService = MPDirectionsService(this)
val directionsRenderer = MPDirectionsRenderer(mMapControl)

val origin = MPPoint(57.057917, 9.950361, 0.0)
val destination = MPPoint(57.058038, 9.950509, 0.0)

directionsService.setRouteResultListener { route, error ->
route?.let { mpRoute ->
directionsRenderer.setRoute(mpRoute)
}
}

directionsService.query(origin, destination)
}

Controlling the Visible Segments on the Directions Renderer

As previously mentioned, the route object is seperated into objects of MPRouteLeg. Each leg is again separated into 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 legIndex on the MPDirectionsRenderer

void setLegIndex(int position) {
mpDirectionsRenderer.selectLegIndex(position);
}
fun setRouteLegIndex(position: Int) {
mpDirectionsRenderer?.selectLegIndex(position)
}

The length of the legs array from getLegs on the MPRoute object determines the possible values of routeLegIndex (0 ..< length).

Reacting to Label Tapping

Directions Labels refer to the labels shown at the end of the rendered route segment path, that may provide contextual information, or show instructions for a required user action at that point. The labels are created as simple Marker instances that are rendered as markers on the map. A user is able to long press these, and an event will be forwarded to the listener OnLegSelectedListener in MPDirectionsRenderer. This can be used to change the Leg to the next Leg in line on the Route.

void getRoute() {
MPDirectionsService directionsService = new MPDirectionsService(this);
MPDirectionsRenderer directionsRenderer = new MPDirectionsRenderer(mMapControl);

MPPoint origin = new MPPoint(57.057917, 9.950361, 0.0);
MPPoint destination = new MPPoint(57.058038, 9.950509, 0.0);

directionsService.setRouteResultListener((route, error) -> {
if (route != null) {
directionsRenderer.setRoute(route);
}
});

directionsRenderer.setOnLegSelectedListener(i -> {
directionsRenderer.selectLegIndex(i);
});

directionsService.query(origin, destination);
}
fun getRoute() {
val directionsService = MPDirectionsService(this)
val directionsRenderer = MPDirectionsRenderer(mMapControl)

val origin = MPPoint(57.057917, 9.950361, 0.0)
val destination = MPPoint(57.058038, 9.950509, 0.0)

directionsService.setRouteResultListener { route, error ->
route?.let { mpRoute ->
directionsRenderer.setRoute(mpRoute)
}
}

directionsRenderer.setOnLegSelectedListener {
mpDirectionsRenderer?.selectLegIndex(it)
}

directionsService.query(origin, destination)
}

MPDirectionsRenderer also has convenience methods to change the active leg to previous and next Leg.

void nextLeg() {
mpDirectionsRenderer.nextLeg();
}

void previousLeg() {
mpDirectionsRenderer.previousLeg();
}
fun nextLeg() {
mpDirectionsRenderer?.nextLeg()
}

fun previousLeg() {
mpDirectionsRenderer?.previousLeg()
}

Show Content of Nearby Locations

It is possible to show contextual information on the end points of the rendered path of a route segment by configuring the directions renderer to look for nearby Locations or POIs.

This is done by creating an appropriate MPContextualInfoSettings object and passing that to the Directions Renderer. If it is not set or is null, no contextual information will be shown.

The MPContextualInfoSetting can be applied on MPDirectionsRenderer by calling useContentOfNearbyLocations(MPContextualInfoSettings). Like this:

//Sets the contextual info to be of locations that has the type "entries" and searches within a max distance of 30 meters from the end point of the current route segment
mpDirectionsRenderer.useContentOfNearbyLocations(new MPContextualInfoSettings.Builder()
.setTypes(Collections.singletonList("entries"))
.setMaxDistance(30.0)
.build());
//Sets the contextual info to be of locations that has the type "entries" and searches within a max distance of 30 meters from the end point of the current route segment
mpDirectionsRenderer?.useContentOfNearbyLocations(MPContextualInfoSettings.Builder()
.setTypes(Collections.singletonList("entries"))
.setMaxDistance(30.0)
.build())

The defaults of the ContextualInfoSettings builder are maxDistance at 5 meters and the ContextualInfoScope as icon and name. No Types or Categories are set as default. Not applying any Types or Categories will make it search through all Locations to use as contextual information.