Audio focus fix for pre Oreo devices (#44)

* Fix audio focus issue encountered on pre Oreo devices

Store a reference to onAudioFocusChangeListener that was used to request audio focus and use it with abandonAudioFocus(..) so that the framework can give back the audio focus to the previous owner.

This fix is relevant to pre Oreo devices.

* Fix test for abandoning audio focus on pre Oreo devices

* Add to Changelog

* Inject OnAudioFocusChangeListener in constructor and avoid use of argument capturer for test consistency

* Update changelog

Co-authored-by: Tejas Nandanikar <[email protected]>

Author: John Qualls

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+### 0.2.1
+
+Bug Fixes
+
+- Fixed a bug where the audio focus wasn't being returned to the previous audio focus owner on pre Oreo devices.
+
 ### 0.2.0
 
 Enhancements

audioswitch/src/main/java/com/twilio/audioswitch/selection/AudioDeviceManager.kt

@@ -17,7 +17,9 @@ internal class AudioDeviceManager(
     private val logger: LogWrapper,
     private val audioManager: AudioManager,
     private val build: BuildWrapper,
-    private val audioFocusRequest: AudioFocusRequestWrapper
+    private val audioFocusRequest: AudioFocusRequestWrapper,
+    private val audioFocusChangeListener: AudioManager.OnAudioFocusChangeListener =
+            AudioManager.OnAudioFocusChangeListener { }
 ) {
 
     private var savedAudioMode = 0
@@ -60,7 +62,7 @@ internal class AudioDeviceManager(
             audioRequest?.let { audioManager.requestAudioFocus(it) }
         } else {
             audioManager.requestAudioFocus(
-                    {},
+                    audioFocusChangeListener,
                     AudioManager.STREAM_VOICE_CALL,
                     AudioManager.AUDIOFOCUS_GAIN_TRANSIENT)
         }
@@ -100,7 +102,7 @@ internal class AudioDeviceManager(
         if (build.getVersion() >= Build.VERSION_CODES.O) {
             audioRequest?.let { audioManager.abandonAudioFocusRequest(it) }
         } else {
-            audioManager.abandonAudioFocus { }
+            audioManager.abandonAudioFocus(audioFocusChangeListener)
         }
     }
 }

audioswitch/src/test/java/com/twilio/audioswitch/bluetooth/BaseTest.kt

@@ -5,6 +5,7 @@ import android.bluetooth.BluetoothClass
 import android.bluetooth.BluetoothDevice
 import android.bluetooth.BluetoothHeadset
 import android.content.Context
+import android.media.AudioManager
 import com.nhaarman.mockitokotlin2.mock
 import com.nhaarman.mockitokotlin2.whenever
 import com.twilio.audioswitch.DEVICE_NAME
@@ -34,8 +35,9 @@ open class BaseTest {
     internal val audioDeviceChangeListener = mock<AudioDeviceChangeListener>()
     internal val buildWrapper = mock<BuildWrapper>()
     internal val audioFocusRequest = mock<AudioFocusRequestWrapper>()
+    internal val audioFocusChangeListener = mock<AudioManager.OnAudioFocusChangeListener>()
     internal val audioDeviceManager = AudioDeviceManager(context, logger, audioManager, buildWrapper,
-            audioFocusRequest)
+            audioFocusRequest, audioFocusChangeListener)
     internal val wiredHeadsetReceiver = WiredHeadsetReceiver(context, logger)
     internal var handler = setupScoHandlerMock()
     internal var systemClockWrapper = setupSystemClockMock()

audioswitch/src/test/java/com/twilio/audioswitch/selection/AudioDeviceSelectorTest.kt

@@ -254,9 +254,9 @@ class AudioDeviceSelectorTest : BaseTest() {
         audioDeviceSelector.activate()
 
         verify(audioManager).requestAudioFocus(
-                isA(),
-                eq(AudioManager.STREAM_VOICE_CALL),
-                eq(AudioManager.AUDIOFOCUS_GAIN_TRANSIENT)
+                audioFocusChangeListener,
+                AudioManager.STREAM_VOICE_CALL,
+                AudioManager.AUDIOFOCUS_GAIN_TRANSIENT
         )
     }
 
@@ -291,7 +291,7 @@ class AudioDeviceSelectorTest : BaseTest() {
         audioDeviceSelector.activate()
         audioDeviceSelector.stop()
 
-        verify(audioManager).abandonAudioFocus(isA())
+        verify(audioManager).abandonAudioFocus(audioFocusChangeListener)
     }
 
     @Test