Is there any way to listen to the event of volume change on Android, without just taking over the volume buttons?
The only thing I've found that works is here, but it works only after the volume control has disappeared.
Not all devices have volume buttons, and I need to capture the volume changes as soon as they occur, and not after the volume dialog is gone.
Note: I'm talking about music/media volume, which is what the OS handles by default when changing volume within apps.
For those using kotlin flows, you can use the following approach to listen to volume changes for a specific stream:
val Context.musicVolumeFlow
get() = callbackFlow {
val receiver = object : BroadcastReceiver() {
override fun onReceive(context: Context, intent: Intent) {
when (intent.getIntExtra("android.media.EXTRA_VOLUME_STREAM_TYPE", 0)) {
AudioManager.STREAM_MUSIC -> trySend(
intent.getIntExtra(
"android.media.EXTRA_VOLUME_STREAM_VALUE",
0
)
)
}
}
}
registerReceiver(receiver, IntentFilter("android.media.VOLUME_CHANGED_ACTION"))
awaitClose { unregisterReceiver(receiver) }
}
You can then collect it as follows from an Activity or Service:
lifecycleScope.launch {
musicVolumeFlow.collect { Log.d("AppLog", "stream volume: $it") }
}
Notice this example is only interested in AudioManager.STREAM_MUSIC. Make sure to target the audio stream relevant to your application.
AudioManager yourself and verify they are defined there. However, it is true those constants are not made public, which is why I had to use the string values explicitly. Considering it's been 12 years and they are still there, I am not too concerned about them being changed or removed, but it's technically true there is no guarantee they will remain available. –
Emad AudioManager.STREAM_MUSIC constant should be used. The example I provided targets AudioManager.STREAM_NOTIFICATION, which means no events would be emitted by adjusting the volume using the hardware keys. –
Emad Better, you can register a ContentObserver as follows:
getApplicationContext().getContentResolver().registerContentObserver(android.provider.Settings.System.CONTENT_URI, true, new ContentObserver(){...} );
Your ContentObserver might look like this:
public class SettingsContentObserver extends ContentObserver {
private AudioManager audioManager;
public SettingsContentObserver(Context context, Handler handler) {
super(handler);
audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
}
@Override
public boolean deliverSelfNotifications() {
return false;
}
@Override
public void onChange(boolean selfChange) {
int currentVolume = audioManager.getStreamVolume(AudioManager.STREAM_MUSIC);
Log.d(TAG, "Volume now " + currentVolume);
}
}
When done:
getApplicationContext().getContentResolver().unregisterContentObserver(mContentObserver);
One caution, though - sometimes the notifications seem to be delayed if there are lots of button presses quickly.
ok , for now , what i do is to listen to the volume buttons using onKeyDown (and check for KEYCODE_VOLUME_DOWN,KEYCODE_VOLUME_MUTE,KEYCODE_VOLUME_UP ) , and using a handler i've posted a new runnable that checks the volume level .
also , since some devices have a volume dialog , i've added a listener to when it is being disappeared , according to this link.
Use broadcast receiver VOLUME_CHANGED_ACTION then use AudioManager to obtain current volume.
<receiver android:name="VolumeChangeReceiver" >
<intent-filter>
<action android:name="android.media.VOLUME_CHANGED_ACTION" />
</intent-filter>
</receiver>
Works with both volume buttons and through Android System UI. I'm using BroadcastReceiver as an Inner Class in this example. I'm using a similar implementation as this to update seek bar in a fragment.
public class AFragment extends Fragment {
private Context context;
private AudioManager audioManager;
// THE STREAM TYPE YOU WANT VOLUME FROM
private final int streamType = AudioManager.STREAM_MUSIC;
private VolumeChangeListener volumeChangeListener;
private IntentFilter intentFilter;
private final String VOLUME_CHANGED_ACTION = "android.media.VOLUME_CHANGED_ACTION";
public AFragment(Context context) {
this.context = context;
this.audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
this.volumeChangeListener = new VolumeChangeListener();
this.intentFilter = new IntentFilter(VOLUME_CHANGED_ACTION);
}
@Override
public void onDestroy() {
super.onDestroy();
context.unregisterReceiver(volumeChangeListener);
}
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
context.registerReceiver(volumeChangeListener, intentFilter);
}
private class VolumeChangeListener extends BroadcastReceiver {
// VOLUME CHANGED ACTION triggers 3 times
// Making use of increment variable to make sure to skip the extra calls
private int callCount = 0;
@Override
public void onReceive(Context context, Intent intent) {
callCount++;
if (intent.getAction().equals(VOLUME_CHANGED_ACTION)) {
if (callCount % 3 == 0) {
int SYSTEM_currentVolume = audioManager.getStreamVolume(streamType);
// DO WHATEVER YOU WANT WITH THE NEW VOLUME VALUE
}
}
}
}
}
IntentFilter android.media.VOLUME_CHANGED_ACTION can be found here: Android Google Source
For those using kotlin flows, you can use the following approach to listen to volume changes for a specific stream:
val Context.musicVolumeFlow
get() = callbackFlow {
val receiver = object : BroadcastReceiver() {
override fun onReceive(context: Context, intent: Intent) {
when (intent.getIntExtra("android.media.EXTRA_VOLUME_STREAM_TYPE", 0)) {
AudioManager.STREAM_MUSIC -> trySend(
intent.getIntExtra(
"android.media.EXTRA_VOLUME_STREAM_VALUE",
0
)
)
}
}
}
registerReceiver(receiver, IntentFilter("android.media.VOLUME_CHANGED_ACTION"))
awaitClose { unregisterReceiver(receiver) }
}
You can then collect it as follows from an Activity or Service:
lifecycleScope.launch {
musicVolumeFlow.collect { Log.d("AppLog", "stream volume: $it") }
}
Notice this example is only interested in AudioManager.STREAM_MUSIC. Make sure to target the audio stream relevant to your application.
AudioManager yourself and verify they are defined there. However, it is true those constants are not made public, which is why I had to use the string values explicitly. Considering it's been 12 years and they are still there, I am not too concerned about them being changed or removed, but it's technically true there is no guarantee they will remain available. –
Emad AudioManager.STREAM_MUSIC constant should be used. The example I provided targets AudioManager.STREAM_NOTIFICATION, which means no events would be emitted by adjusting the volume using the hardware keys. –
Emad You can use : registerMediaButtonEventReceiver (ComponentName eventReceiver) which registers a component to be the sole receiver of MEDIA_BUTTON intents.
// in your activity.
MediaButtonReceiver receiver = new MediaButtonReceiver();
// in onCreate put
registerMediaButtonEventReceiver(receiver);
class MediaButtonReceiver implements BroadcastReceiver {
void onReceive(Intent intent) {
KeyEvent ke = (KeyEvent)intent.getExtra(Intent.EXTRA_KEY_EVENT);
if (ke .getKeyCode() == KeyEvent.KEYCODE_VOLUME_DOWN) {
//action when volume goes down
}
if (ke .getKeyCode() == KeyEvent.KEYCODE_VOLUME_UP) {
//action when volume goes up
}
}
}
//In both onStop and onPause put :
unregisterMediaButtonEventReceiver(receiver);
what we are doing here is defining a BroadcastReceiver that deals with ACTION_MEDIA_BUTTON. and use EXTRA_KEY_EVENT which is containing the key event that caused the broadcast to get what was pressed and act upon that.
© 2022 - 2025 — McMap. All rights reserved.