Android Question Android Auto Support

The audio should be routed to the car speakers automatically when the device is connected. The same is true for the microphone.

Maybe only a Manifest issue than?! I found this:


<application>
...
<meta-data android:name="com.google.android.gms.car.application"
android:resource="@xml/automotive_app_desc"/>
...<application>

From this page:
http://developer.android.com/training/auto/audio/index.html

The first i assume should be like this:
AddApplicationText(<activity android:name="com.google.android.gms.car.application"/>)

But how do i translate the android:resource="@xml/automotive_app_desc"/> in B4A?

Have you tried to play any music while the device is connected to the car? It should work automatically.

I tried to to start another music app after connection to Android Auto, and than the sound from that app is in my Head Unit emulator too. So your right. But if I play a mp3 from my B4A app, the sound doesn't go anywhere. I'm using the MediaPlayer.

If i start to play a mp3 song from a player, and at the same time play a sound from my app, the sound from my app also goes through.

I also tried to ReInitialize (Release and Initialize) before play, but with no difference.

Have you tried to call the code from this thread: https://www.b4x.com/android/forum/threads/tts-with-bluetooth-headset.27814/#post-161450 ?

Yes! I have used that code for a long time in my app in my old car that didn't have android auto. Works very good, interrupts the current audio as it is a phone call, and the audio goes out of my speaker with "phone" quality. Actually, my first plan with the new car was to have two phones connected, one only for google maps navigation in android auto, and the other phone like i had it in my old car. But that didn't work. When having a phone connected to android auto, volkswagen doesn't allow another phone to be connected to bluetooth at the same time. (Having 2 phones connected at the same time on bluetooth is a new feature of the MIB2 in the Volkswagen MQB platform)

Actually, after upgrading to Lollipop it stopped working, so after some reversed engineering I ended up with this:

r.Target = r.GetContext
r.Target = r.RunMethod2("getSystemService", "audio", "java.lang.String")
r.RunMethod("startBluetoothSco")
r.RunMethod2("setMode", 3, "java.lang.int")
r.RunMethod2("setSpeakerphoneOn", True, "java.lang.boolean")
For n = 1 To 2
Sleep(1000)
Next
r.RunMethod2("setBluetoothScoOn", True,"java.lang.boolean")

But, still not work when connected to Android Auto.....
(Of course have I tried totally without the code above also...)

Am I the only one who have interest in this topic?

I have tested several other apps now, and it seems like it is only sound from B4A created app that doesn't go to the Android Auto Head Unit.
But common for all apps, is that the App must be started After the device is connected to the Head Unit, otherwise no sound at all.

B4A doesn't do anything special. It just loads the audio file and plays it with MediaPlayer.

Try to use Phone.VOLUME_VOICE_CALL stream instead of the default stream:

With your code above, the sounds goes to the earphone regardless if I'm connected to the Head Unit or not. I have tested with Tasker, and have the same problem. I've tried all the stream outputs, "Call", "system", "alarm" goes to the phonespeaker. "Ringer" and "Notification" goes nowhere.

Well, seems that we are stuck here. If I understand you correct Erel, it should just work, but for me it doesn't. So is it the Mediaplayer that doesn't support Android Auto? Seems like that (see my previous post) because I didn't make it work with Tasker either. Although, I'm seem to be the anyone who has interest of getting this to work, so i assume that the issue has low priority.

B4A MediaPlayer is a thin wrapper over the native MediaPlayer.
The API mentioned here: http://developer.android.com/training/auto/audio/index.html is currently not available in any B4A library.