Enable navigation for CarPlay

This section describes how you can use the Navigation SDK with the Apple CarPlay library to display your app's navigation experience on in-dash head units. If a driver's in-dash system supports CarPlay, 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.

You build your CarPlay app from a set of UI templates provided by Apple. Your app is responsible for selecting the template to show and for providing the data inside of it.

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

The CarPlay and phone navigation displays
The left-hand image shows an example of a CarPlay navigation display. The right-hand image shows the same navigation as it appears on a phone.

Setup

Start with CarPlay

First, familiarize yourself with the Apple documentation:

Set up the Navigation SDK

  1. Once you've read through the Apple documentation, you're ready to work with the Navigation SDK.
  2. Set up your project if you haven't already integrated the Navigation SDK into your app.
  3. Enable the TurnByTurn guidance feed for your app.
  4. Optional. Use generated icons from the Navigation SDK.
  5. Draw the map using the GMSMapView class provided in the UIView class. See Navigate a route for more information. Populate CPNavigationSession with the data from the TurnByTurn library.

Draw the map and navigation UI

The GMSMapView class renders a map and the CPMapTemplate renders the UI on CarPlay screens. It provides much of the same functionality as the GMSMapView for phones, but with limited interactivity.

Swift

init(window: CPWindow) {
    super.init(nibName: nil, bundle: nil)
    self.window = window

    // More CPMapTemplate initialization

}

override func viewDidLoad() {
    super.viewDidLoad()

    let mapViewOptions = GMSMapViewOptions()
    mapViewOptions.screen = window.screen
    mapViewOptions.frame = self.view.bounds

    mapView = GMSMapView(options: mapViewOptions)
    mapView.autoresizingMask = [.flexibleHeight, .flexibleWidth]
    mapView.settings.isNavigationHeaderEnabled = false
    mapView.settings.isNavigationFooterEnabled = false

    // Disable buttons: in CarPlay, no part of the map is clickable.
    // The app should instead place these buttons in the appropriate slots of the CarPlay template.
    mapView.settings.compassButton = false
    mapView.settings.isRecenterButtonEnabled = false
    mapView.shouldDisplaySpeedometer = false
    mapView.isMyLocationEnabled = true

    self.view.addSubview(mapView)
}

Objective-C

- (instancetype)initWithWindow:(CPWindow *)window {
  self = [super initWithNibName:nil bundle:nil];
  if (self) {
    _window = window;

  // More CPMapTemplate initialization
  }
}

- (void)viewDidLoad {
  [super viewDidLoad];
  GMSMapViewOptions *options = [[GMSMapViewOptions alloc] init];
  options.screen = _window.screen;
  options.frame = self.view.bounds;
  _mapView = [[GMSMapView alloc] initWithOptions:options];
  _mapView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
  _mapView.settings.navigationHeaderEnabled = NO;
  _mapView.settings.navigationFooterEnabled = NO;

  // Disable buttons: in CarPlay, no part of the map is clickable.
  // The app should instead place these buttons in the appropriate slots of the CarPlay template.
  _mapView.settings.compassButton = NO;
  _mapView.settings.recenterButtonEnabled = NO;

  _mapView.shouldDisplaySpeedometer = NO;
  _mapView.myLocationEnabled = YES;

  [self.view addSubview:_mapView];
}

Enable map interaction

To ensure driver safety, CarPlay limits screen surface interaction to a series of CPMapTemplateDelegate methods. Use these callbacks to support limited driver interaction with the map on an in-dash screen.

To support additional user actions, create an array of CPMapButton and assign it toCPMapTemplate.mapButtons.

The following code creates panning interactions and buttons to pan, zoom in and out, and to provide the user's location.

Panning interactions

Swift

// MARK: CPMapTemplateDelegate
func mapTemplate(_ mapTemplate: CPMapTemplate, panBeganWith direction: CPMapTemplate.PanDirection) {

}

func mapTemplate(_ mapTemplate: CPMapTemplate, panWith direction: CPMapTemplate.PanDirection) {
    let scrollAmount = scrollAmount(for: direction)
    let scroll = GMSCameraUpdate.scrollBy(x: scrollAmount.x, y: scrollAmount.y)
    mapView.animate(with: scroll)
}

func mapTemplate(_ mapTemplate: CPMapTemplate, panEndedWith direction: CPMapTemplate.PanDirection) {
}

func scrollAmount(for panDirection: CPMapTemplate.PanDirection) -> CGPoint {
    let scrollDistance = 80.0
    var scrollAmount = CGPoint(x: 0, y: 0)
    switch panDirection {
        case .left:
            scrollAmount.x -= scrollDistance
            break;
        case .right:
            scrollAmount.x += scrollDistance
            break;
        case .up:
            scrollAmount.y += scrollDistance
            break;
        case .down:
            scrollAmount.y -= scrollDistance
            break;
        default:
            break;
    }
    if scrollAmount.x != 0 && scrollAmount.y != 0 {
        // Adjust length if scrolling diagonally.
        scrollAmount = CGPointMake(scrollAmount.x * sqrt(1.0/2.0), scrollAmount.y * sqrt(1.0/2.0))
    }
    return scrollAmount
}

Objective-C

#pragma mark - CPMapTemplateDelegate

- (void)mapTemplate:(CPMapTemplate *)mapTemplate panBeganWithDirection:(CPPanDirection)direction {
}

- (void)mapTemplate:(CPMapTemplate *)mapTemplate panWithDirection:(CPPanDirection)direction {
CGPoint scrollAmount = [self scrollAmountForPanDirection:direction];
GMSCameraUpdate *scroll = [GMSCameraUpdate scrollByX:scrollAmount.x Y:scrollAmount.y];
[_mapView animateWithCameraUpdate:scroll];
}

- (void)mapTemplate:(CPMapTemplate *)mapTemplate panEndedWithDirection:(CPPanDirection)direction {
}
- (CGPoint)scrollAmountForPanDirection:(CPPanDirection)direction {
  static const CGFloat scrollDistance = 80.;
  CGPoint scrollAmount = {0., 0.};
  if (direction & CPPanDirectionLeft) {
    scrollAmount.x = -scrollDistance;
  }
  if (direction & CPPanDirectionRight) {
    scrollAmount.x = scrollDistance;
  }
  if (direction & CPPanDirectionUp) {
    scrollAmount.y = -scrollDistance;
  }
  if (direction & CPPanDirectionDown) {
    scrollAmount.y = scrollDistance;
  }
  if (scrollAmount.x != 0 && scrollAmount.y != 0) {
  // Adjust length if scrolling diagonally.
  scrollAmount =
    CGPointMake(scrollAmount.x * (CGFloat)M_SQRT1_2, scrollAmount.y * (CGFloat)M_SQRT1_2);
  }
  return scrollAmount;
}

Common button usages

Swift

// MARK: Create Buttons

func createMapButtons() -> [CPMapButton] {
    let panButton = mapButton(systemImageName: "dpad.fill") { [weak self] in
        self?.didTapPanButton()
    }

    let zoomOutButton = mapButton(systemImageName: "minus.magnifyingglass") { [weak self] in
        self?.didTapZoomOutButton()
    }

    let zoomInButton = mapButton(systemImageName: "plus.magnifyingglass") { [weak self] in
        self?.didTapZoomInButton()
    }

    let myLocationButton = mapButton(systemImageName: "location") { [weak self] in
        self?.didTapMyLocationButton()
    }

    let mapButtons = [panButton, zoomOutButton, zoomInButton, myLocationButton]
    return mapButtons
}

func mapButton(systemImageName: String, handler: @escaping () -> Void) -> CPMapButton {

}


// MARK: Button callbacks

@objc func didTapPanButton() {
    mapTemplate?.showPanningInterface(animated: true)
}

@objc func didTapZoomOutButton() {
    mapView.animate(with: GMSCameraUpdate.zoomOut())
}

@objc func didTapZoomInButton() {
    mapView.animate(with: GMSCameraUpdate.zoomIn())
}

@objc func didTapMyLocationButton() {
    if let lastLocation = lastLocation {
        let cameraPosition = GMSCameraPosition(target: lastLocation.coordinate, zoom: 15)
        mapView.animate(to: cameraPosition)
    }
}

Objective-C

#pragma mark - Create Buttons

- (NSArray<CPMapButton *>*)createMapButtons {
    NSMutableArray<CPMapButton *> *mapButtons = [NSMutableArray<CPMapButton *> array];

    __weak __typeof__(self) weakSelf = self;
    CPMapButton *panButton = [self mapButtonWithSystemImageNamed:@"dpad.fill"
                                                        handler:^(CPMapButton *_) {
                                                        [weakSelf didTapPanButton];
                                                        }];
    [mapButtons addObject:panButton];

    CPMapButton *zoomOutButton =
        [self mapButtonWithSystemImageNamed:@"minus.magnifyingglass"
                                    handler:^(CPMapButton *_Nonnull mapButon) {
                                    [weakSelf didTapZoomOutButton];
                                    }];
    [mapButtons addObject:zoomOutButton];

    CPMapButton *zoomInButton =
        [self mapButtonWithSystemImageNamed:@"plus.magnifyingglass"
                                    handler:^(CPMapButton *_Nonnull mapButon) {
                                    [weakSelf didTapZoomInButton];
                                    }];
    [mapButtons addObject:zoomInButton];

    CPMapButton *myLocationButton =
        [self mapButtonWithSystemImageNamed:@"location"
                                    handler:^(CPMapButton *_Nonnull mapButton) {
                                    [weakSelf didTapMyLocationButton];
                                    }];
    [mapButtons addObject:myLocationButton];
    return mapButtons;
}

#pragma mark - Button Callbacks

- (void)didTapZoomOutButton {
[_mapView animateWithCameraUpdate:[GMSCameraUpdate zoomOut]];
}

- (void)didTapZoomInButton {
[_mapView animateWithCameraUpdate:[GMSCameraUpdate zoomIn]];
}

- (void)didTapMyLocationButton {
CLLocation *location = self.lastLocation;
if (location) {
    GMSCameraPosition *position =
        [[GMSCameraPosition alloc] initWithTarget:self.lastLocation.coordinate zoom:15.];
    [_mapView animateToCameraPosition:position];
}
}

- (void)didTapPanButton {
[_mapTemplate showPanningInterfaceAnimated:YES];
_isPanningInterfaceEnabled = YES;
}

- (void)didTapStopPanningButton {
[_mapTemplate dismissPanningInterfaceAnimated:YES];
_isPanningInterfaceEnabled = NO;
}

Note: Alternate routes cannot be selected on the CarPlay screen. They must be selected from the phone before CarPlay starts.

Display navigation directions

This section covers how to set up a listener for a data feed and how to populate navigation directions in the guidance and trip estimate panels. See the "Build a CarPlay Navigation App" section of the CarPlay App Programming Guide for more information.

Guidance and trip estimate panels provide a navigation card that displays navigation information related to the current trip. The TurnByTurn library in Navigation SDK can help provide some of this information, such as symbol, text, and remaining time.

Set up a listener

Follow the instructions for setting up an event listener in Details about the turn-by-turn data feed.

Populate navigation information

The first portion of the following code sample shows how to create CarPlay travel estimates by translating the GMSNavigationNavInfo.timeToCurrentStepSeconds to CPTravelEstimate. You can read more about these and other display elements in Details about the turn-by-turn data feed.

The second part of the sample shows how to create an object and store it in the userInfo field of CPManuevers. This determines the CPManeuverDisplayStyle, which is also used for lane guidance information. See Apple's CarPlay App Programming Guide for more information.

Swift

// Get a CPTravelEstimate from GMSNavigationNavInfo
func getTravelEstimates(from navInfo:GMSNavigationNavInfo) -> CPTravelEstimates {
    let distanceRemaining = navInfo.roundedDistance(navInfo.distanceToCurrentStepMeters)
    let timeRemaining = navInfo.roundedTime(navInfo.timeToCurrentStepSeconds)
    let travelEstimates = CPTravelEstimates(distanceRemaining: distanceRemaining, timeRemaining: timeRemaining)
    return travelEstimates
}

//  Create an object to be stored in the userInfo field of CPManeuver to determine the CPManeuverDisplayStyle. 

/** An object to be stored in the userInfo field of a CPManeuver. */

struct ManeuverUserInfo {
    var stepInfo: GMSNavigationStepInfo
    var isLaneGuidance: Bool
}

func mapTemplate(_ mapTemplate: CPMapTemplate, displayStyleFor maneuver: CPManeuver) -> CPManeuverDisplayStyle {
    let userInfo = maneuver.userInfo
    if let maneuverUserInfo = userInfo as? ManeuverUserInfo {
        return maneuverUserInfo.isLaneGuidance ? .symbolOnly : .leadingSymbol
    }
    return .leadingSymbol
}

// Get a CPManeuver with instructionVariants and symbolImage from GMSNavigationStepInfo
func getManeuver(for stepInfo: GMSNavigationStepInfo) -> CPManeuver {
    let maneuver = CPManeuver()
    maneuver.userInfo = ManeuverUserInfo(stepInfo: stepInfo, isLaneGuidance: false)
    switch stepInfo.maneuver {
        case .destination:
            maneuver.instructionVariants = ["Your destination is ahead."]
            break
        case .destinationLeft:
            maneuver.instructionVariants = ["Your destination is ahead on your left."]
            break
        case .destinationRight:
            maneuver.instructionVariants = ["Your destination is ahead on your right."]
            break
        default:
            maneuver.attributedInstructionVariants = currentNavInfo?.instructions(forStep: stepInfo, options: instructionOptions)
            break
    }
    maneuver.symbolImage = stepInfo.maneuverImage(with: instructionOptions.imageOptions)
    return maneuver
}

// Get the lane image for a CPManeuver from GMSNavigationStepInfo
func laneGuidanceManeuver(for stepInfo: GMSNavigationStepInfo) -> CPManeuver? {
    let maneuver = CPManeuver()
    maneuver.userInfo = ManeuverUserInfo(stepInfo: stepInfo, isLaneGuidance: true)
    let lanesImage = stepInfo.lanesImage(with: imageOptions)
    guard let lanesImage = lanesImage else { return nil }
    maneuver.symbolImage = lanesImage
    return maneuver
}

Objective-C

// Get a CPTravelEstimate from GMSNavigationNavInfo
- (nonull CPTravelEstimates *)travelEstimates:(GMSNavigationNavInfo *_Nonnull navInfo) {
NSMeasurement<NSUnitLength *> *distanceRemaining = [navInfo roundedDistance:navInfo.distanceToCurrentStepMeters];
NSTimeInterval timeRemaining = [navInfo roundedTime:navInfo.timeToCurrentStepSeconds];
CPTravelEstimate* travelEstimate = [[CPTravelEstimates alloc] initWithDistanceRemaining:distanceRemaining
                                                timeRemaining:timeRemaining];
}
//  Create an object to be stored in the userInfo field of CPManeuver to determine the CPManeuverDisplayStyle. 

/** An object to be stored in the userInfo field of a CPManeuver. */
@interface ManeuverUserInfo : NSObject

@property(nonatomic, readonly, nonnull) GMSNavigationStepInfo *stepInfo;
@property(nonatomic, readonly, getter=isLaneGuidance) BOOL laneGuidance;

- (nonnull instancetype)initWithStepInfo:(GMSNavigationStepInfo *)stepInfo
                        isLaneGuidance:(BOOL)isLaneGuidance NS_DESIGNATED_INITIALIZER;

- (instancetype)init NS_UNAVAILABLE;

@end

- (CPManeuverDisplayStyle)mapTemplate:(CPMapTemplate *)mapTemplate
            displayStyleForManeuver:(nonnull CPManeuver *)maneuver {
ManeuverUserInfo *userInfo = maneuver.userInfo;
return userInfo.laneGuidance ? CPManeuverDisplayStyleSymbolOnly : CPManeuverDisplayStyleDefault;
}
// Get a CPManeuver with instructionVariants and symbolImage from GMSNavigationStepInfo
- (nonnull CPManeuver *)maneuverForStep:(nonnull GMSNavigationStepInfo *)stepInfo {
CPManeuver *maneuver = [[CPManeuver alloc] init];
maneuver.userInfo = [[ManeuverUserInfo alloc] initWithStepInfo:stepInfo isLaneGuidance:NO];
switch (stepInfo.maneuver) {
    case GMSNavigationManeuverDestination:
    maneuver.instructionVariants = @[ @"Your destination is ahead." ];
    break;
    case GMSNavigationManeuverDestinationLeft:
    maneuver.instructionVariants = @[ @"Your destination is ahead on your left." ];
    break;
    case GMSNavigationManeuverDestinationRight:
    maneuver.instructionVariants = @[ @"Your destination is ahead on your right." ];
    break;
    default: {
    maneuver.attributedInstructionVariants =
        [_currentNavInfo instructionsForStep:stepInfo options:_instructionOptions];
    break;
    }
}
maneuver.symbolImage = [stepInfo maneuverImageWithOptions:_instructionOptions.imageOptions];
return maneuver;
}
// Get the lane image for a CPManeuver from GMSNavigationStepInfo
- (nullable CPManeuver *)laneGuidanceManeuverForStep:(nonnull GMSNavigationStepInfo *)stepInfo {
CPManeuver *maneuver = [[CPManeuver alloc] init];
maneuver.userInfo = [[ManeuverUserInfo alloc] initWithStepInfo:stepInfo isLaneGuidance:YES];
UIImage *lanesImage = [stepInfo lanesImageWithOptions:_imageOptions];
if (!lanesImage) {
    return nil;
}
maneuver.symbolImage = lanesImage;
return maneuver;
}

Maneuvers

CarPlay uses the CPManeuver class to provide turn-by-turn guidance. See Details about the turn-by-turn data feed for more information on maneuvers and lane guidance.