Android Auto - Drive Your Car, Use Your Phone, and Don't Hurt Anyone

Curious about Android Auto? Announced at Google I/O 2014, Android Auto is Google’s attempt to bring Android to the car, with controls and a user interface optimized for driving. The first cars with Auto support were released in the summer of 2015 and Google has now opened up Android Auto to everyone with the recent release of the Android Auto app, giving developers a unique opportunity to reach a whole new set of users. The goal of this session is to get you started developing great apps for this emerging platform.

We’ll talk about how to:
- Extend your existing audio or messaging app to be compatible with an Android Auto head unit;

- Use Android Auto to play music, compose and read messages and respond to user voice actions;

- Develop and test your apps with the Desktop Head Unit;

- Make sense of the Android Auto design guidelines and usability requirements that are in place for Auto apps;

- Distribute your Auto app through Google Play.

Join us as we walk through real-life examples and see just how easy it is to get started with Android Auto!

Transcript

1. Android Auto Drive Your Car, Use Your Phone, and Don’t Hurt Anyone Phil Shadlyn @physphil #ChicagoRoboto
2. #ChicagoRoboto @physphil What is Android Auto? • Safely use your device while driving • Limited functionality • Voice control
3. #ChicagoRoboto @physphil What ISN’T Android Auto? • Not a standalone version of Android • No Google Play Store • Can only use Auto-compatible apps
6. #ChicagoRoboto @physphil A Brief History • Announced at Google I/O 2014 • 2015 Hyundai Sonata was first to implement • Adoption increased through 2015 and 2016 • Android Auto v2.0 released in November 2016
7. #ChicagoRoboto @physphil Limited Functionality • Navigation • Telephony • Messaging • Audio Control • Web Search
8. #ChicagoRoboto @physphil Requirements • Android 5.0+ device • Download Android Auto app • Car with Android Auto head unit (optional)
9. #ChicagoRoboto @physphil Basic Operation • Connect phone to car / open Android Auto app • Phone goes into “Auto mode” • Phone or Head Unit displays series of contextual cards • Microphone button triggers voice actions • Activity bar to start specific apps
10. #ChicagoRoboto @physphil Auto mode Voice actions Activity bar Contextual info
11. #ChicagoRoboto @physphil Let’s take a tour...
12. #ChicagoRoboto @physphil Home Screen Left: Head Unit Right: Phone
13. #ChicagoRoboto @physphil Navigation Left: Head Unit Right: Phone
14. #ChicagoRoboto @physphil Telephony
15. #ChicagoRoboto @physphil Messaging
16. #ChicagoRoboto @physphil Audio Control Left: Head Unit Right: Phone
17. #ChicagoRoboto @physphil How do I make an app for Auto?
18. #ChicagoRoboto @physphil You don’t.
19. #ChicagoRoboto @physphil Cool, let’s go to the party
20. #ChicagoRoboto @physphil Developing Apps for Auto • Extend existing apps - think Chromecast, Android Wear • Currently can only extend Audio or Messaging apps • targetSdkVersion 21+ • No UI code!
21. #ChicagoRoboto @physphil Create automotive_app_desc.xml config file <automotiveApp> <uses name="media"/> <uses name="notification"/> </automotiveApp> Add to <application> in manifest <meta-data android:name="com.google.android.gms.car.application" android:resource="@xml/automotive_app_desc" /> Developing Apps for Auto
22. Extending a Messaging App https://developer.android.com/training/auto/messaging/index.html
23. #ChicagoRoboto @physphil • Extend existing notification objects with CarExtender • Provide Intents to be triggered when messages are heard and replied to • Above Intents trigger BroadcastReceivers, which can update app • RemoteInput object captures reply spoken by driver Extending a Messaging App
24. #ChicagoRoboto @physphil // Create Intent to be triggered when user hears message final Intent messageHeardIntent = new Intent(); messageHeardIntent.setAction("com.physphil.android.ACTION_MESSAGE_HEARD"); messageHeardIntent.addFlags(Intent.FLAG_INCLUDE_STOPPED_PACKAGES); messageHeardIntent.putExtra("message_id", message.getId()); // Create PendingIntent to trigger above intent final PendingIntent messageHeardPendingIntent = PendingIntent.getBroadcast(getApplicationContext(), message.getId(), messageHeardIntent, PendingIntent.FLAG_UPDATE_CURRENT); Handle “Message Heard” Action
25. #ChicagoRoboto @physphil Handle “Message Reply” Action // Create Intent to be triggered when user replies message final Intent messageReplyIntent = new Intent(); messageReplyIntent.setAction("com.physphil.android.ACTION_MESSAGE_REPLY"); messageReplyIntent.addFlags(Intent.FLAG_INCLUDE_STOPPED_PACKAGES); messageReplyIntent.putExtra("message_id", message.getId()); // Create PendingIntent to trigger above intent final PendingIntent messageReplyPendingIntent = PendingIntent.getBroadcast(getApplicationContext(), message.getId(), messageHeardIntent, PendingIntent.FLAG_UPDATE_CURRENT); // Create RemoteInput to capture spoken reply RemoteInput remoteInput = new RemoteInput.Builder("key_voice_reply").build();
26. #ChicagoRoboto @physphil Add Unread Messages to UnreadConversation // Create UnreadConversation object for all unread messages to display UnreadConversation.Builder unreadConversation = new UnreadConversation.Builder(conversation.getSenderName()) .setReadPendingIntent(messageHeardPendingIntent) .setReplyAction(messageReplyPendingIntent, remoteInput); // Add each unread message for (Message message : conversation.getUnreadMessages()) { unreadConversation.addMessage(message.getText()) .setLatestTimestamp(message.getTimestamp()); }
27. #ChicagoRoboto @physphil Great, now what?
28. #ChicagoRoboto @physphil Extend Existing Notification // Generate Notification NotificationCompat.Builder builder = new NotificationCompat.Builder(this) .setSmallIcon(R.drawable.ic_stat_notification) .setContentIntent(pendingIntent) .setAutoCancel(true) .setLargeIcon(BitmapFactory.decodeResource(getResources(), R.drawable.icon)) .setContentTitle(getString(R.string.new_message)) .setContentText(message.getText()); NotificationManager notificationManager = getSystemService(NOTIFICATION_SERVICE); notificationManager.notify(NOTIFICATION_ID, builder.build());
29. #ChicagoRoboto @physphil Extend Existing Notification // Generate Notification NotificationCompat.Builder builder = new NotificationCompat.Builder(this) .setSmallIcon(R.drawable.ic_stat_notification) .setContentIntent(pendingIntent) .setAutoCancel(true) .setLargeIcon(BitmapFactory.decodeResource(getResources(), R.drawable.icon)) .setContentTitle(getString(R.string.new_message)) .setContentText(message.getText()) .extend(new NotificationCompat.CarExtender() .setUnreadConversation(unreadConversation.build())); NotificationManagerCompat notificationManager = NotificationManagerCompat.from(this); notificationManager.notify(NOTIFICATION_ID, builder.build());
30. #ChicagoRoboto @physphil <receiver android:name=".MessageHeardReceiver" android:enabled="true" android:exported="true"> <intent-filter> <action android:name="com.physphil.android.ACTION_MESSAGE_HEARD"/> </intent-filter> </receiver> <receiver android:name=".MessageReplyReceiver" android:enabled="true" android:exported="true"> <intent-filter> <action android:name="com.physphil.android.ACTION_MESSAGE_REPLY" /> </intent-filter> </receiver> Define BroadcastReceivers in AndroidManifest.xml
31. #ChicagoRoboto @physphil Extract Reply and Send Message public class MessageReplyReceiver extends BroadcastReceiver { @Override public void onReceive(Context context, Intent intent) { // Get message id final int id = intent.getIntExtra("message_id", -1); // Get voice reply and send reply through our messaging app final Bundle ri = RemoteInput.getResultsFromIntent(intent); if (ri != null) { final CharSequence reply = ri.getCharSequence("key_voice_reply"); MessageService.getInstance().sendReply(id, reply); } } }
32. Extending an Audio App https://developer.android.com/training/auto/audio/index.html
33. #ChicagoRoboto @physphil • MediaSession.Callback implements playback controls • Extend MediaBrowserService to provide content hierarchy • Register for voice actions with IntentFilter in manifest • Examples and best practices found in Universal Music Player https://github.com/googlesamples/android-UniversalMusicPlayer Extending an Audio App
34. Android Auto triggers MediaSession callbacks onGetRoot() returns root node and session token onLoadChildren() called to provide media hierarchy
35. #ChicagoRoboto @physphil Ok… so how do I do this?
36. #ChicagoRoboto @physphil Implement MediaSession.Callback public void onPlay() public void onPlayFromMediaId(String mediaId, Bundle extras) public void onPlayFromSearch(String query, Bundle extras) public void onPlayFromUri(Uri uri, Bundle extras) public void onPause() public void onStop() public void onSkipToNext() public void onSkipToPrevious() public void onSkipToQueueItem(long id) public void onRewind() public void onFastForward() public void onSeekTo(long pos)
37. #ChicagoRoboto @physphil Register for Voice Actions <!-- Use this intent filter to get voice searches, like "Play The Beatles" --> <intent-filter> <action android:name="android.media.action.MEDIA_PLAY_FROM_SEARCH" /> <category android:name="android.intent.category.DEFAULT" /> </intent-filter> Attach to launcher activity
38. #ChicagoRoboto @physphil And what about this MediaBrowserService?
39. #ChicagoRoboto @physphil Basic Workflow • Register MediaSession in onCreate() • onGetRoot() called to get top node of content hierarchy • onLoadChildren() gets media in root node • onLoadChildren() called again for each selected sub node • MediaSession.Callback invoked when user plays media
40. #ChicagoRoboto @physphil Extend MediaBrowserService <service android:name=".MusicService" android:exported="true"> <intent-filter> <action android:name="android.media.browse.MediaBrowserService" /> </intent-filter> </service> Define Service in AndroidManifest.xml
41. #ChicagoRoboto @physphil Implement onGetRoot() @Override public BrowserRoot onGetRoot(@NonNull String clientPackageName, int clientUid, Bundle rootHints) { // Verify the app attempting to access media contents if (!mPackageValidator.isCallerAllowed(this, clientPackageName, clientUid)) { // If the request comes from an untrusted package, return empty root. return new MediaBrowserServiceCompat.BrowserRoot(MEDIA_ID_EMPTY_ROOT, null); } return new BrowserRoot(MEDIA_ID_ROOT, null); }
42. #ChicagoRoboto @physphil Implement onLoadChildren @Override public void onLoadChildren(@NonNull final String parentMediaId, @NonNull final Result<List<MediaItem>> result) { if (parentMediaId.equals(MEDIA_ID_EMPTY_ROOT)) { result.sendResult(new ArrayList<MediaItem>()); } else if (mMusicProvider.isInitialized()) { // if music library is ready, return immediately result.sendResult(mMusicProvider.getChildren(parentMediaId, getResources())); } else { // otherwise, only return results when the music library is retrieved result.detach(); mMusicProvider.retrieveMediaAsync(new MusicProvider.Callback() { @Override public void onMusicCatalogReady(boolean success) { result.sendResult(mMusicProvider.getChildren(parentMediaId, getResources())); } }); } }
43. #ChicagoRoboto @physphil Testing and Distribution
44. #ChicagoRoboto @physphil Testing • Enable Developer Options in Auto app to test on phone • Use Desktop Head Unit to simulate in-car dashboard • Use alpha/beta Play Store channels to test in actual car
45. #ChicagoRoboto @physphil Auto App Quality • Review Auto App Quality checklist before publication https://developer.android.com/develop/quality-guidelines/auto-app-quality.html ◦ Must support voice actions ◦ Only pertinent notifications ◦ Only short-form messaging (ie no email clients) ◦ Touch actions must be complete within 6 steps ◦ No visual ads ◦ No animations, images or scrolling text ◦ No games
46. #ChicagoRoboto @physphil Google Play Distribution • All apps subject to driver safety review, even updates • On failure, notified via email with a list of deficiencies • App will not be published until successful review
47. #ChicagoRoboto @physphil Want to Learn More? • Android Auto Developer Site https://developer.android.com/training/auto/index.html • Android Auto DevBytes https://www.youtube.com/watch?t=1&v=ctiaVxgclsg • Android Auto Udacity Course https://www.udacity.com/course/android-auto-development--ud875C • Distribute to Android Auto https://developer.android.com/distribute/best-practices/launch/distribute-auto.html
48. Questions? Phil Shadlyn @physphil #ChicagoRoboto