How to set Audio Focus ChangeListener in Android API O?

Question

Since requestAudioFocus(AudioManager.OnAudioFocusChangeListener l, int streamType, int durationHint) is deprecated in API O , how do you set audio focus change list

Answer 1

Another option is to use AudiomanagerCompat together with AudioAttributesCompat and AudioRequestCompat, all part of Jetpack (androidx) compatibility libraries: https://developer.android.com/reference/androidx/media/AudioManagerCompat

In this way, you can use the same code for Android O+ and also for previous versions (without conditional checks on the API version. But one of the drawbacks of this approach is that you can't use: .setAcceptsDelayedFocusGain(true)

If you decide for this approach, then you have to use requestAudioFocus(mAudioManager, mFocusRequest) and abandonAudioFocusRequest(mAudioManager, mFocusRequest) to obtain and release audio focus.

Partial sample code (in Kotlin): (Note: if you do not use Timber for logging, replace it by the standard Log function)

class MyClass : AudioManager.OnAudioFocusChangeListener {

    internal var audioManager: AudioManager? = null
    private var focusRequest: AudioFocusRequestCompat? = null
    private var playbackAttributes : AudioAttributesCompat? = null

    // Create AudioManager and other audio related objects
    audioManager = getSystemService(Context.AUDIO_SERVICE) as AudioManager?
    playbackAttributes = AudioAttributesCompat.Builder()
                .setUsage(AudioAttributesCompat.USAGE_MEDIA)
                .setContentType(AudioAttributesCompat.CONTENT_TYPE_SPEECH)
                .build()

    focusRequest = AudioFocusRequestCompat.Builder(AudioManagerCompat.AUDIOFOCUS_GAIN)
                .setAudioAttributes(playbackAttributes ?: return)
                .setWillPauseWhenDucked(false)
                .setOnAudioFocusChangeListener(this)
                .build()

    // Request audio focus and check if it was granted to us
    if (requestAudioFocus(audioManager!!, focusRequest!!) == AudioManager.AUDIOFOCUS_REQUEST_GRANTED) {
         // We obtained audio focus

    }
    else {
        // We could not obtain audio focus

    }

    // And to remove audio focus
    if (audioManager != null && focusRequest != null)
            abandonAudioFocusRequest(audioManager!!, focusRequest!!)



    // Implementation of OnAudioFocusChangeListener
    override fun onAudioFocusChange(focusState: Int) {

        // Invoked when the audio focus of the system is updated.
        when (focusState) {
            AudioManager.AUDIOFOCUS_GAIN -> {
                // We recovered audio focus.
                Timber.d("Audio Focus obtained")
            }
            AudioManager.AUDIOFOCUS_LOSS -> {
                // Lost focus for an unbounded amount of time
                Timber.d("Audio Focus lost")
            }
            AudioManager.AUDIOFOCUS_LOSS_TRANSIENT_CAN_DUCK -> {
                // Lost focus for a short time, but it's ok to keep playing at an attenuated level
                Timber.d("Audio Focus transient loss - can duck")
            }
            AudioManager.AUDIOFOCUS_LOSS_TRANSIENT -> {
                // Lost focus for a short time
                Timber.d("Audio Focus transient loss - cannot duck")
            }
        }
    }
}