Enable navigation for Android Auto

This section describes how you can use the Navigation SDK with the Android for Cars App library to display your app's navigation experience on in-dash head units. If a driver's in-dash system supports Android Auto, drivers can use your app directly on their car's display by connecting their phone to the unit. Voice guidance also runs on the car's speakers.

An in-dash head unit that displays guided navigation using an app enabled
for Android Auto.

The Android for Cars App Library enables Android applications to run on Android Auto by providing a set of visual templates approved for driver safety. These templates purposefully restrict the in-dashboard UI controls from those of the phone in order to reduce driver distraction.

When you enable your Navigation SDK-powered app to work with Android Auto, you provide an additional view for the navigation experience. This allows for two map views—one for the phone and one for the head unit. Both displays receive guidance from Navigator.java, which is a singleton.

The in-dashboard system displays the safety approved interactive elements so that the driver can safely navigate to their destination without undue distraction. The driver can also interact with your app-specific functionality, such as accepting or rejecting orders, or viewing the location of the customer on a map. Order status updates can also appear on the in-dashboard unit.

An in-dash head unit that displays turn-by-turn guidance with Android
Auto. An Android phone that displays the same route as an overview.

The attached phone can continue displaying the standard Navigation SDK experience or any other view or workflow in your application. This allows you to continue to provide custom functionality that might not work well on a car screen.

Set up

The first part of getting your app working with Android Auto involves setting up a car service with Android Auto and then enabling the TurnByTurn library in your Navigation SDK app.

Start with Android Auto

Before you begin working with the Navigation SDK features designed to work with Android Auto, you must set up a car service for your app so that Android Auto can discover it.

Follow these steps, all of which can be found in the Android for Cars developers documentation:

  1. Familiarize yourself with the basic Android Auto features.
  2. Install the Android for Cars App Library.
  3. Configure your app's manifest file to include Android Auto.
  4. Declare a minimum car-app level of 1 in your manifest.
  5. Create your CarAppService and session.

Set up the Navigation SDK

Once you have established your car app service, you're ready to work with the Navigation SDK.

  1. Set up your project, if you haven't already integrated the Navigation SDK into your app.
  2. Enable the TurnbyTurn guidance feed for your app.
  3. Optional. Use generated icons from the Navigation SDK.
  4. Draw the map using the NavigationViewForAuto class on the Android Auto Surface provided in the Screen class.
  5. Populate the Android Auto Navigation template with the data from the TurnbyTurn library.

Now that you have a registered service for providing navigation information to your app and your app can connect to Android Auto, you're ready to create the rest of the navigation elements necessary for your app to work properly with Android Auto:

Draw the map and navigation UI

The NavigationViewForAuto class renders a map and navigation UI on Android Auto screens. It provides much of the same functionality as the NavigationView for phones, but with limited interactivity. Use NavigationViewForAuto to draw onto the Surface provided by Android Auto:

private boolean isSurfaceReady(SurfaceContainer surfaceContainer) {
  return surfaceContainer.getSurface() != null
        && surfaceContainer.getDpi() != 0
        && surfaceContainer.getHeight() != 0
        && surfaceContainer.getWidth() != 0;
}

@Override
public void onSurfaceAvailable(@NonNull SurfaceContainer surfaceContainer) {
  if (!isSurfaceReady(surfaceContainer)) {
    return;
   }
  virtualDisplay =
      getCarContext()
          .getSystemService(DisplayManager.class)
          .createVirtualDisplay(
            VIRTUAL_DISPLAY_NAME,
            surfaceContainer.getWidth(),
            surfaceContainer.getHeight(),
            surfaceContainer.getDpi(),
            surfaceContainer.getSurface(),
            DisplayManager.VIRTUAL_DISPLAY_FLAG_OWN_CONTENT_ONLY);
    presentation = new Presentation(getCarContext(), virtualDisplay.getDisplay());

    navigationView = new NavigationViewForAuto(getCarContext());
    navigationView.onCreate(null);
    navigationView.onStart();
    navigationView.onResume();

    presentation.setContentView(navigationView);
    presentation.show();

    navigationView.getMapAsync(googleMap -> this.googleMap = googleMap);
  }

@Override
public void onSurfaceDestroyed(@NonNull SurfaceContainer surfaceContainer) {
  navigationView.onPause();
  navigationView.onStop();
  navigationView.onDestroy();

  presentation.dismiss();
  virtualDisplay.release();
}

Enable map interaction

To ensure driver safety, Android Auto limits screen surface interaction to a series of SurfaceCallback methods. Use these callbacks to support limited driver interaction with the map on an in-dash screen. For example, onClick and onScale correspond to tap and pinch gestures from the user. Interactivity callbacks must use the map action strip as follows:

  • To receive map interactivity callbacks, your app must use an Action.PAN button.

  • To support additional user actions, add buttons to the map action strip.

Enable surface callbacks

@NonNull
@Override
public Template onGetTemplate() {
  return new NavigationTemplate.Builder()
    .setActionStrip(new ActionStrip.Builder().build())
    .setMapActionStrip(new ActionStrip.Builder().addAction(Action.PAN).build())
    .build();
}

Zoom with pinch

@Override
public void onScale(float focusX, float focusY, float scaleFactor) {
  CameraUpdate update =
      CameraUpdateFactory.zoomBy((scaleFactor - 1),
                                  new Point((int) focusX, (int) focusY));
  googleMap.animateCamera(update); // map is set in onSurfaceAvailable.
}

Panning

@Override
public void onScroll(float distanceX, float distanceY) {
  googleMap.moveCamera(CameraUpdateFactory.scrollBy(distanceX, distanceY));
}

Display navigation directions

This section covers how to set up an observer for navigation posts and to populate navigation directions in the turn card template.

A turn card for Android Auto
guidance.

The Android Auto Navigation Template provides a turn card that displays navigation information related to the current trip. The TurnByTurn library in Navigation SDK provides this navigation information, which your code uses to populate the Android Auto navigation template.

Set up an observer

In the following example, SampleApplication is a custom application class that maintains a MutableLiveData<NavInfo> object. When the observer receives an update from the navigator object, it posts this NavInfo object to the NavInfoMutableLiveData maintained by the SampleApplication class.

The following example registers an observer for this object in its implementation of the Android Auto Screen.

public SampleAndroidAutoNavigationScreen(@NonNull CarContext carContext,
                                     SampleApplication application) {
  super(carContext);
  getCarContext().getCarService(AppManager.class).setSurfaceCallback(this);
  application.getNavInfoMutableLiveData().observe(this, this::processNextStep);
}

Populate navigation information

The following code snippet shows how to populate the Android Auto template with the current routing information, including steps, distances, and icons. You can read more about these display elements in Populate the feed display.

Expand to see the code example.

private RoutingInfo currentRoutingInfo;

@NonNull
@Override
public Template onGetTemplate() {
NavigationTemplate.Builder navigationTemplateBuilder =
  new NavigationTemplate.Builder()
    .setActionStrip(...)
    .setMapActionStrip(...)
  if (currentRoutingInfo != null) {
    navigationTemplateBuilder.setNavigationInfo(currentRoutingInfo);
  }
  return navigationTemplateBuilder.build();
}

private void processNextStep(NavInfo navInfo) {
  if (navInfo == null || navinfo.getCurrentStep() == null) {
    return;
  }

/**
*   Converts data received from the Navigation data feed
*   into Android-Auto compatible data structures. For more information
*   see the "Ensure correct maneuver types" below.
*/
  Step currentStep = buildStepFromStepInfo(navInfo.getCurrentStep());
  Distance distanceToStep =
              buildDistanceFromMeters(navInfo.getDistanceToCurrentStepMeters());

  currentRoutingInfo =
     new RoutingInfo.Builder().setCurrentStep(currentStep, distanceToStep).build();

  // Invalidate the current template which leads to another onGetTemplate call.
  invalidate();
}

private Step buildStepFromStepInfo(StepInfo stepInfo) {
  IconCompat maneuverIcon =
               IconCompat.createWithBitmap(stepInfo.getManeuverBitmap());
  Maneuver.Builder
            maneuverBuilder = newManeuver.Builder(
                  ManeuverConverter
                          .getAndroidAutoManeuverType(stepInfo.getManeuver()));
  CarIcon maneuverCarIcon = new CarIcon.Builder(maneuverIcon).build();
  maneuverBuilder.setIcon(maneuverCarIcon);
  Step.Builder stepBuilder =
    new Step.Builder()
       .setRoad(stepInfo.getFullRoadName())
       .setCue(stepInfo.getFullInstructionText())
       .setManeuver(maneuverBuilder.build());

  if (stepInfo.getLanes() != null
           && stepInfo.getLanesBitmap() != null) {
    for (Lane lane : buildAndroidAutoLanesFromStep(stepInfo)) {
      stepBuilder.addLane(lane);
    }
    IconCompat lanesIcon =
               IconCompat.createWithBitmap(stepInfo.getLanesBitmap());
    CarIcon lanesImage = new CarIcon.Builder(lanesIcon).build();
    stepBuilder.setLanesImage(lanesImage);
  }
    return stepBuilder.build();
}

/*
*   Constructs a {@code Distance} object in imperial measurement units.
*   In a real world scenario, units would be based on locale.
*/
private Distance buildDistanceFromMeters(int distanceMeters) {

// Distance can be negative so set the min distance to 0.
  int remainingFeet = (int) max(0, distanceMeters * DistanceConstants.FEET_PER_METER);
  double remainingMiles = ((double) remainingFeet) / DistanceConstants.FEET_PER_MILE;

// Only use the tenths place digit if distance is less than 10 miles and show
// feet if distance is less than 0.25 miles.

  if (remainingMiles >= DistanceConstants.MIN_MILES_TO_SHOW_INTEGER) {
    return Distance.create((int) round(remainingMiles), Distance.UNIT_MILES);
  } else if (remainingMiles >= 0.25) {
    return Distance.create((int) remainingMiles, Distance.UNIT_MILES);
  } else {
    return Distance.create(remainingFeet, Distance.UNIT_FEET);
  }
}

Ensure correct maneuver types

The kinds of maneuvers used in the Android Auto Car library correspond one-to-one to maneuvers provided by the TurnByTurn library. However, you must convert the Navigation SDK maneuvers to a valid declaration in the Android Auto Car library. The following table shows the correspondence for a handful of fields, followed by a sample converter utility for your convenience.

Turn-by-Turn Library Maneuver Android Auto Maneuver
DEPART TYPE_DEPART
DESTINATION TYPE_DESTINATION
DESTINATION_LEFT TYPE_DESTINATION_LEFT
DESTINATION_RIGHT TYPE_DESTINATION_RIGHT
TURN_U_TURN_CLOCKWISE TYPE_U_TURN_RIGHT
ON_RAMP_LEFT TYPE_ON_RAMP_NORMAL_LEFT
ON_RAMP_RIGHT TYPE_ON_RAMP_NORMAL_RIGHT
ON_RAMP_SLIGHT_LEFT TYPE_ON_RAMP_SLIGHT_LEFT
FORK_RIGHT TYPE_FORK_RIGHT

Expand to see the code example.

import com.google.android.libraries.mapsplatform.turnbyturn.model.Maneuver;
import com.google.common.collect.ImmutableMap;
import javax.annotation.Nullable;

/** Converter that converts between turn-by-turn and Android Auto Maneuvers. */
public final class ManeuverConverter {
  private ManeuverConverter() {}

  // Map from turn-by-turn Maneuver to Android Auto Maneuver.Type.
  private static final ImmutableMap<Integer, Integer> MANEUVER_TO_ANDROID_AUTO_MANEUVER_TYPE =
      ImmutableMap.<Integer, Integer>builder()
          .put(Maneuver.DEPART, androidx.car.app.navigation.model.Maneuver.TYPE_DEPART)
          .put(Maneuver.DESTINATION, androidx.car.app.navigation.model.Maneuver.TYPE_DESTINATION)
          .put(
              Maneuver.DESTINATION_LEFT,
              androidx.car.app.navigation.model.Maneuver.TYPE_DESTINATION_LEFT)
          .put(
              Maneuver.DESTINATION_RIGHT,
              androidx.car.app.navigation.model.Maneuver.TYPE_DESTINATION_RIGHT)
          .put(Maneuver.STRAIGHT, androidx.car.app.navigation.model.Maneuver.TYPE_STRAIGHT)
          .put(Maneuver.TURN_LEFT, androidx.car.app.navigation.model.Maneuver.TYPE_TURN_NORMAL_LEFT)
          .put(
              Maneuver.TURN_RIGHT,
              androidx.car.app.navigation.model.Maneuver.TYPE_TURN_NORMAL_RIGHT)
          .put(Maneuver.TURN_KEEP_LEFT, androidx.car.app.navigation.model.Maneuver.TYPE_KEEP_LEFT)
          .put(Maneuver.TURN_KEEP_RIGHT, androidx.car.app.navigation.model.Maneuver.TYPE_KEEP_RIGHT)
          .put(
              Maneuver.TURN_SLIGHT_LEFT,
              androidx.car.app.navigation.model.Maneuver.TYPE_TURN_SLIGHT_LEFT)
          .put(
              Maneuver.TURN_SLIGHT_RIGHT,
              androidx.car.app.navigation.model.Maneuver.TYPE_TURN_SLIGHT_RIGHT)
          .put(
              Maneuver.TURN_SHARP_LEFT,
              androidx.car.app.navigation.model.Maneuver.TYPE_TURN_SHARP_LEFT)
          .put(
              Maneuver.TURN_SHARP_RIGHT,
              androidx.car.app.navigation.model.Maneuver.TYPE_ON_RAMP_SHARP_RIGHT)
          .put(
              Maneuver.TURN_U_TURN_CLOCKWISE,
              androidx.car.app.navigation.model.Maneuver.TYPE_U_TURN_RIGHT)
          .put(
              Maneuver.TURN_U_TURN_COUNTERCLOCKWISE,
              androidx.car.app.navigation.model.Maneuver.TYPE_U_TURN_LEFT)
          .put(
              Maneuver.MERGE_UNSPECIFIED,
              androidx.car.app.navigation.model.Maneuver.TYPE_MERGE_SIDE_UNSPECIFIED)
          .put(Maneuver.MERGE_LEFT, androidx.car.app.navigation.model.Maneuver.TYPE_MERGE_LEFT)
          .put(Maneuver.MERGE_RIGHT, androidx.car.app.navigation.model.Maneuver.TYPE_MERGE_RIGHT)
          .put(Maneuver.FORK_LEFT, androidx.car.app.navigation.model.Maneuver.TYPE_FORK_LEFT)
          .put(Maneuver.FORK_RIGHT, androidx.car.app.navigation.model.Maneuver.TYPE_FORK_RIGHT)
          .put(
              Maneuver.ON_RAMP_UNSPECIFIED,
              androidx.car.app.navigation.model.Maneuver.TYPE_ON_RAMP_NORMAL_RIGHT)
          .put(
              Maneuver.ON_RAMP_LEFT,
              androidx.car.app.navigation.model.Maneuver.TYPE_ON_RAMP_NORMAL_LEFT)
          .put(
              Maneuver.ON_RAMP_RIGHT,
              androidx.car.app.navigation.model.Maneuver.TYPE_ON_RAMP_NORMAL_RIGHT)
          .put(
              Maneuver.ON_RAMP_KEEP_LEFT,
              androidx.car.app.navigation.model.Maneuver.TYPE_ON_RAMP_NORMAL_LEFT)
          .put(
              Maneuver.ON_RAMP_KEEP_RIGHT,
              androidx.car.app.navigation.model.Maneuver.TYPE_ON_RAMP_NORMAL_RIGHT)
          .put(
              Maneuver.ON_RAMP_SLIGHT_LEFT,
              androidx.car.app.navigation.model.Maneuver.TYPE_ON_RAMP_SLIGHT_LEFT)
          .put(
              Maneuver.ON_RAMP_SLIGHT_RIGHT,
              androidx.car.app.navigation.model.Maneuver.TYPE_ON_RAMP_SLIGHT_RIGHT)
          .put(
              Maneuver.ON_RAMP_SHARP_LEFT,
              androidx.car.app.navigation.model.Maneuver.TYPE_ON_RAMP_SHARP_LEFT)
          .put(
              Maneuver.ON_RAMP_SHARP_RIGHT,
              androidx.car.app.navigation.model.Maneuver.TYPE_ON_RAMP_SHARP_RIGHT)
          .put(
              Maneuver.ON_RAMP_U_TURN_CLOCKWISE,
              androidx.car.app.navigation.model.Maneuver.TYPE_ON_RAMP_U_TURN_RIGHT)
          .put(
              Maneuver.ON_RAMP_U_TURN_COUNTERCLOCKWISE,
              androidx.car.app.navigation.model.Maneuver.TYPE_ON_RAMP_U_TURN_LEFT)
          .put(
              Maneuver.OFF_RAMP_LEFT,
              androidx.car.app.navigation.model.Maneuver.TYPE_OFF_RAMP_NORMAL_LEFT)
          .put(
              Maneuver.OFF_RAMP_RIGHT,
              androidx.car.app.navigation.model.Maneuver.TYPE_OFF_RAMP_NORMAL_RIGHT)
          .put(
              Maneuver.OFF_RAMP_KEEP_LEFT,
              androidx.car.app.navigation.model.Maneuver.TYPE_OFF_RAMP_SLIGHT_LEFT)
          .put(
              Maneuver.OFF_RAMP_KEEP_RIGHT,
              androidx.car.app.navigation.model.Maneuver.TYPE_OFF_RAMP_SLIGHT_RIGHT)
          .put(
              Maneuver.OFF_RAMP_SLIGHT_LEFT,
              androidx.car.app.navigation.model.Maneuver.TYPE_OFF_RAMP_SLIGHT_LEFT)
          .put(
              Maneuver.OFF_RAMP_SLIGHT_RIGHT,
              androidx.car.app.navigation.model.Maneuver.TYPE_OFF_RAMP_SLIGHT_RIGHT)
          .put(
              Maneuver.OFF_RAMP_SHARP_LEFT,
              androidx.car.app.navigation.model.Maneuver.TYPE_OFF_RAMP_NORMAL_LEFT)
          .put(
              Maneuver.OFF_RAMP_SHARP_RIGHT,
              androidx.car.app.navigation.model.Maneuver.TYPE_OFF_RAMP_NORMAL_RIGHT)
          .put(
              Maneuver.ROUNDABOUT_CLOCKWISE,
              androidx.car.app.navigation.model.Maneuver.TYPE_ROUNDABOUT_ENTER_AND_EXIT_CW)
          .put(
              Maneuver.ROUNDABOUT_COUNTERCLOCKWISE,
              androidx.car.app.navigation.model.Maneuver.TYPE_ROUNDABOUT_ENTER_AND_EXIT_CCW)
          .put(
              Maneuver.ROUNDABOUT_STRAIGHT_CLOCKWISE,
              androidx.car.app.navigation.model.Maneuver.TYPE_ROUNDABOUT_ENTER_CW)
          .put(
              Maneuver.ROUNDABOUT_STRAIGHT_COUNTERCLOCKWISE,
              androidx.car.app.navigation.model.Maneuver.TYPE_ROUNDABOUT_ENTER_CCW)
          .put(
              Maneuver.ROUNDABOUT_LEFT_CLOCKWISE,
              androidx.car.app.navigation.model.Maneuver
                  .TYPE_ROUNDABOUT_ENTER_AND_EXIT_CW_WITH_ANGLE)
          .put(
              Maneuver.ROUNDABOUT_LEFT_COUNTERCLOCKWISE,
              androidx.car.app.navigation.model.Maneuver
                  .TYPE_ROUNDABOUT_ENTER_AND_EXIT_CCW_WITH_ANGLE)
          .put(
              Maneuver.ROUNDABOUT_RIGHT_CLOCKWISE,
              androidx.car.app.navigation.model.Maneuver
                  .TYPE_ROUNDABOUT_ENTER_AND_EXIT_CW_WITH_ANGLE)
          .put(
              Maneuver.ROUNDABOUT_RIGHT_COUNTERCLOCKWISE,
              androidx.car.app.navigation.model.Maneuver
                  .TYPE_ROUNDABOUT_ENTER_AND_EXIT_CCW_WITH_ANGLE)
          .put(
              Maneuver.ROUNDABOUT_SLIGHT_LEFT_CLOCKWISE,
              androidx.car.app.navigation.model.Maneuver
                  .TYPE_ROUNDABOUT_ENTER_AND_EXIT_CW_WITH_ANGLE)
          .put(
              Maneuver.ROUNDABOUT_SLIGHT_LEFT_COUNTERCLOCKWISE,
              androidx.car.app.navigation.model.Maneuver
                  .TYPE_ROUNDABOUT_ENTER_AND_EXIT_CCW_WITH_ANGLE)
          .put(
              Maneuver.ROUNDABOUT_SLIGHT_RIGHT_CLOCKWISE,
              androidx.car.app.navigation.model.Maneuver
                  .TYPE_ROUNDABOUT_ENTER_AND_EXIT_CW_WITH_ANGLE)
          .put(
              Maneuver.ROUNDABOUT_SLIGHT_RIGHT_COUNTERCLOCKWISE,
              androidx.car.app.navigation.model.Maneuver
                  .TYPE_ROUNDABOUT_ENTER_AND_EXIT_CCW_WITH_ANGLE)
          .put(
              Maneuver.ROUNDABOUT_SHARP_LEFT_CLOCKWISE,
              androidx.car.app.navigation.model.Maneuver
                  .TYPE_ROUNDABOUT_ENTER_AND_EXIT_CW_WITH_ANGLE)
          .put(
              Maneuver.ROUNDABOUT_SHARP_LEFT_COUNTERCLOCKWISE,
              androidx.car.app.navigation.model.Maneuver
                  .TYPE_ROUNDABOUT_ENTER_AND_EXIT_CCW_WITH_ANGLE)
          .put(
              Maneuver.ROUNDABOUT_SHARP_RIGHT_CLOCKWISE,
              androidx.car.app.navigation.model.Maneuver
                  .TYPE_ROUNDABOUT_ENTER_AND_EXIT_CW_WITH_ANGLE)
          .put(
              Maneuver.ROUNDABOUT_SHARP_RIGHT_COUNTERCLOCKWISE,
              androidx.car.app.navigation.model.Maneuver
                  .TYPE_ROUNDABOUT_ENTER_AND_EXIT_CCW_WITH_ANGLE)
          .put(
              Maneuver.ROUNDABOUT_U_TURN_CLOCKWISE,
              androidx.car.app.navigation.model.Maneuver
                  .TYPE_ROUNDABOUT_ENTER_AND_EXIT_CW_WITH_ANGLE)
          .put(
              Maneuver.ROUNDABOUT_U_TURN_COUNTERCLOCKWISE,
              androidx.car.app.navigation.model.Maneuver
                  .TYPE_ROUNDABOUT_ENTER_AND_EXIT_CCW_WITH_ANGLE)
          .put(
              Maneuver.ROUNDABOUT_EXIT_CLOCKWISE,
              androidx.car.app.navigation.model.Maneuver.TYPE_ROUNDABOUT_EXIT_CW)
          .put(
              Maneuver.ROUNDABOUT_EXIT_COUNTERCLOCKWISE,
              androidx.car.app.navigation.model.Maneuver.TYPE_ROUNDABOUT_EXIT_CCW)
          .put(Maneuver.FERRY_BOAT, androidx.car.app.navigation.model.Maneuver.TYPE_FERRY_BOAT)
          .put(Maneuver.FERRY_TRAIN, androidx.car.app.navigation.model.Maneuver.TYPE_FERRY_TRAIN)
          .put(Maneuver.NAME_CHANGE, androidx.car.app.navigation.model.Maneuver.TYPE_NAME_CHANGE)
          .buildOrThrow();

  /** Represents the roundabout turn angle for a slight turn in either right or left directions. */
  private static final int ROUNDABOUT_ANGLE_SLIGHT = 10;

  /** Represents the roundabout turn angle for a normal turn in either right or left directions. */
  private static final int ROUNDABOUT_ANGLE_NORMAL = 45;

  /** Represents the roundabout turn angle for a sharp turn in either right or left directions. */
  private static final int ROUNDABOUT_ANGLE_SHARP = 135;

  /** Represents the roundabout turn angle for a u-turn in either right or left directions. */
  private static final int ROUNDABOUT_ANGLE_U_TURN = 180;

  /**
   * Returns the corresponding {@link androidx.car.app.navigation.model.Maneuver.Type} for the given
   * direction {@link Maneuver}
   *
   * @throws {@link IllegalArgumentException} if the given maneuver does not have a corresponding
   *     Android Auto Maneuver type.
   */
  public static int getAndroidAutoManeuverType(@Maneuver int maneuver) {
    if (MANEUVER_TO_ANDROID_AUTO_MANEUVER_TYPE.containsKey(maneuver)) {
      return MANEUVER_TO_ANDROID_AUTO_MANEUVER_TYPE.get(maneuver);
    }
    throw new IllegalArgumentException(
        String.format(
            "Given turn-by-turn Maneuver %d cannot be converted to an Android Auto equivalent.",
            maneuver));
  }

  /**
   * Returns the corresponding Android Auto roundabout angle for the given turn {@link Maneuver}.
   * Returns {@code null} if given maneuver does not involve a roundabout with a turn.
   */
  @Nullable
  public static Integer getAndroidAutoRoundaboutAngle(@Maneuver int maneuver) {
    if (maneuver == Maneuver.ROUNDABOUT_LEFT_CLOCKWISE
        || maneuver == Maneuver.ROUNDABOUT_RIGHT_CLOCKWISE
        || maneuver == Maneuver.ROUNDABOUT_LEFT_COUNTERCLOCKWISE
        || maneuver == Maneuver.ROUNDABOUT_RIGHT_COUNTERCLOCKWISE) {
      return ROUNDABOUT_ANGLE_NORMAL;
    }
    if (maneuver == Maneuver.ROUNDABOUT_SHARP_LEFT_CLOCKWISE
        || maneuver == Maneuver.ROUNDABOUT_SHARP_RIGHT_CLOCKWISE
        || maneuver == Maneuver.ROUNDABOUT_SHARP_LEFT_COUNTERCLOCKWISE
        || maneuver == Maneuver.ROUNDABOUT_SHARP_RIGHT_COUNTERCLOCKWISE) {
      return ROUNDABOUT_ANGLE_SHARP;
    }
    if (maneuver == Maneuver.ROUNDABOUT_SLIGHT_LEFT_CLOCKWISE
        || maneuver == Maneuver.ROUNDABOUT_SLIGHT_RIGHT_CLOCKWISE
        || maneuver == Maneuver.ROUNDABOUT_SLIGHT_LEFT_COUNTERCLOCKWISE
        || maneuver == Maneuver.ROUNDABOUT_SLIGHT_RIGHT_COUNTERCLOCKWISE) {
      return ROUNDABOUT_ANGLE_SLIGHT;
    }
    if (maneuver == Maneuver.ROUNDABOUT_U_TURN_CLOCKWISE
        || maneuver == Maneuver.ROUNDABOUT_U_TURN_COUNTERCLOCKWISE) {
      return ROUNDABOUT_ANGLE_U_TURN;
    }
    return null;
  }
}