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Voice Instruction Simulated Navigation

In this guide you will learn how to simulate navigation along a computed route rendered on an interactive map, from a departure position to a desired destination.
The map is fully 3D, supporting pan, pinch-zoom, rotate and tilt.
The navigation includes voice instructions in a language of your choice.

Setup

First, get an API key token, see the Getting Started guide.
Download the Maps & Navigation SDK for Android archive file

Download the VoiceInstrRouteSimulation project archive file or clone the project with Git

See the Configure Android Example guide.

Run the example

In Android Studio, from the File menu, select Sync Project with Gradle Files

Voice instruction simulated navigation example Android screenshot

An android device should be connected via USB cable.
Press SHIFT+F10 to compile, install and run the example on the android device.

How it works

Android example screenshot

You can open the MainActivity.kt file to see how simulated navigation along a computed route with voice instructions works.

1private val navigationService = NavigationService()

A NavigationService() is instantiated, which carries out both simulated navigation and real navigation.

 1private val navigationListener: NavigationListener = NavigationListener.create(
 2     onNavigationStarted = { onNavigationStarted() },
 3     onNavigationSound = { sound ->
 4         SdkCall.execute {
 5             SoundPlayingService.play(sound, playingListener, soundPreference)
 6         }
 7     },
 8     canPlayNavigationSound = true,
 9     postOnMain = true
10)
The NavigationListener receives event updates during navigation such as when the destination is reached, or when the route to the desired destination has been recomputed, because a detour away from the original route was taken.
Besides the onNavigationStarted listener, the onNavigationSound listener is also instantiated, to receive the voice instructions for turns and other events along the route, including warnings, such as about speed cameras or exceeding the posted speed limit.
1private val routingProgressListener = ProgressListener.create(
2     onStarted = {
3         progressBar.visibility = View.VISIBLE
4     },
5     onCompleted = { _, _ ->
6         progressBar.visibility = View.GONE
7     },
8     postOnMain = true
9)
Define a listener to indicate when the route computation is completed, so real or simulated navigation (simulated in this case) can start.
 1private fun onNavigationStarted() = SdkCall.execute {
 2     gemSurfaceView.mapView?.let { mapView ->
 3         mapView.preferences?.enableCursor = false
 4         navigationService.getNavigationRoute(navigationListener)?.let { route ->
 5             mapView.presentRoute(route)
 6         }
 7         enableGPSButton()
 8         mapView.followPosition()
 9     }
10}
When navigation is started, mapView.followPosition() causes the camera to follow the green arrow.
If the user pans (moves) the map to another location, the camera no longer follows the green arrow.

Voice instruction simulated navigation example Android screenshot

 1private fun enableGPSButton() {
 2     // Set actions for entering/ exiting following position mode.
 3     gemSurfaceView.mapView?.apply {
 4         onExitFollowingPosition = {
 5             followCursorButton.visibility = View.VISIBLE
 6         }
 7         onEnterFollowingPosition = {
 8             followCursorButton.visibility = View.GONE
 9         }
10         // Set on click action for the GPS button.
11         followCursorButton.setOnClickListener {
12             SdkCall.execute { followPosition() }
13         }
14     }
15}
enableGPSButton() causes a round purple button to appear in the lower right corner of the screen, whenever the simulation is active and the camera is not following the green arrow. If the user pushes this button, the followPosition() function is called, and thus the camera starts to follow the green arrow once again.
1private fun startSimulation() = SdkCall.execute {
2     val waypoints = arrayListOf(
3         Landmark("Start", 48.526, 7.734),
4         Landmark("Destination", 41.645, -0.883)
5     )
6     navigationService.startSimulation(waypoints, navigationListener, routingProgressListener)
7}
The starting, or departure point of the route is the first waypoint in a list of 2 or more Landmarks (2 in this case), each containing a name, latitude (in degrees) and longitude (in degrees). The destination point is the last waypoint in the list.
 1override fun onCreate(savedInstanceState: Bundle?) {
 2    super.onCreate(savedInstanceState)
 3    setContentView(R.layout.activity_main)
 4    progressBar = findViewById(R.id.progressBar)
 5    gemSurfaceView = findViewById(R.id.gem_surface)
 6    followCursorButton = findViewById(R.id.followCursor)
 7
 8    SdkSettings.onMapDataReady = onMapDataReady@{ isReady ->
 9         if (!isReady) return@onMapDataReady
10
11         SdkCall.execute {
12             contentStore = ContentStore()
13
14             val type = EContentType.HumanVoice
15             val countryCode = "IRL"
16             val onVoiceReady = { voiceFilePath: String ->
17                 SdkSettings.setVoiceByPath(voiceFilePath)
18                 startSimulation()
19             }
20             // check if already exists locally
21             contentStore?.getLocalContentList(type)?.let { localList ->
22                 for (item in localList) {
23                     if (item.countryCodes?.contains(countryCode) == true) {
24                         onVoiceReady(item.filename!!)
25                         return@execute // already exists
26                     }
27                 }
28             }
29             // download the voice
30             contentStore?.asyncGetStoreContentList(type, onCompleted =
31             { result, _, _ ->
32                 SdkCall.execute {
33                     for (item in result) {
34                         if (item.countryCodes?.contains(countryCode) == true) {
35                             item.asyncDownload(onCompleted = { _, _ ->
36                                 SdkCall.execute {
37                                     onVoiceReady(item.filename!!)
38                                 }
39                             })
40                             break
41                         }
42                     }
43                 }
44             })
The MainActivity overrides the onCreate() function which downloads the voice from the server to be used for the voice instructions during the simulated navigation.
Note the 3-letter ISO countrycode val countryCode = "IRL" to specify which voice to download.
A complete list of these country codes can be found here:
https://en.wikipedia.org/wiki/ISO_3166-1_alpha-3

Android Examples

Maps SDK for Android Examples can be downloaded or cloned with Git