Handle bluetooth headset clicks (ACTION_VOICE_COMMAND and ACTION_WEB_SEARCH) on Android

Question

I’m developing an Android application and I want it to interact with headset button clicks. I’m testing it in a Nexus 5 with Android KitKat 4.4.

I tried first with a simple headset (not wireless). The button event received was KEYCODE_HEADSETHOOK (79). I created a MEDIA_BUTTON receiver to handle its clicks:

<receiver android:name="com.example.mytest.SearchActivity$MediaButtonIntentReceiver">
    <intent-filter>
        <intent-filter android:priority="1000000000">
            <action android:name="android.intent.action.MEDIA_BUTTON" />
        </intent-filter>
    </intent-filter>
</receiver>

This is the activity holding the receiver:

public class SearchActivity extends Activity {

    private AudioManager mAudioManager;
    private ComponentName mAudioReceiver;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.search);

        mAudioManager = (AudioManager) getSystemService(AUDIO_SERVICE);
        mAudioReceiver =  new ComponentName(getPackageName(),
            MediaButtonIntentReceiver.class.getName());
    }

    @Override
    protected void onResume() {
        super.onResume();

        mAudioManager.registerMediaButtonEventReceiver(mAudioReceiver);
    }

    @Override
    protected void onPause() {
        super.onPause();

        mAudioManager.unregisterMediaButtonEventReceiver(mAudioReceiver);
    }

    public static class MediaButtonIntentReceiver extends BroadcastReceiver {

        @Override
        public void onReceive(Context context, Intent intent) {
            Log.d("SA", "ON RECEIVE");

            ...

            abortBroadcast();
        }
    }
}

This code works with my wired headset only if the user performs a short click. Performing a long click opens Google Voice Search. I’d like to capture long clicks too, but I don’t mind if it’s not possible.

After that I tested it with a bluetooth headset. Specifically, I’m using Moveteck Bluetooth Headset BH119A (you can see an image at the bottom of this post). This headset only has one button, and if I press it the following "activity" is opened:

I’d like to capture this click event too if my Activity is opened. How can I do it? I tried adding the following filters to my receiver, but it’s not working either:

<action android:name="android.bluetooth.headset.action.VENDOR_SPECIFIC_HEADSET_EVENT" />
<action android:name="android.intent.action.VOICE_COMMAND" />
<action android:name="android.intent.action.CALL_BUTTON" />

I also tried overriding onKeyDown in my Activity, but it’s not triggered.

Anybody knows how can I intercept those events?

This is my bluetooth headset:

---

** EDIT **

Following Toaster’s advice, I checked the whole log looking for the events my headset triggers.

Wired headset long click

This is the log when I long click in my wired headset (it opens Google Voice Search):

12-10 09:24:36.644: I/MediaFocusControl(740): voice-based interactions: about to use ACTION_WEB_SEARCH
12-10 09:24:36.644: I/ActivityManager(740): START u0 {act=android.speech.action.WEB_SEARCH flg=0x10800000 cmp=com.google.android.googlequicksearchbox/.SearchActivity} from pid 740
12-10 09:24:36.754: I/ActivityManager(740): START u0 {act=android.speech.action.WEB_SEARCH flg=0x10000000 cmp=com.google.android.googlequicksearchbox/com.google.android.launcher.GEL} from pid 10153
12-10 09:24:36.764: I/InputDispatcher(740): Dropping event because there is no focused window or focused application.
12-10 09:24:36.764: I/InputDispatcher(740): Dropping event because there is no focused window or focused application.
12-10 09:24:36.774: I/GEL(1025): handleIntent(Intent { act=android.speech.action.WEB_SEARCH flg=0x10400000 cmp=com.google.android.googlequicksearchbox/com.google.android.launcher.GEL })
12-10 09:24:36.774: V/SearchControllerCache(10153): creating SearchController
12-10 09:24:36.804: I/AudioRouter(10153): ROUTE_NONE->ROUTE_NO_BLUETOOTH
12-10 09:24:36.804: I/MediaFocusControl(740):  AudioFocus  requestAudioFocus() from android.media.AudioManager@4267ad58com.google.android.voicesearch.audio.AudioRouterImpl$1@42695f60
12-10 09:24:36.804: I/Velvet.SdchManager(10153): Sdch cache load complete.
12-10 09:24:36.814: W/IInputConnectionWrapper(18407): showStatusIcon on inactive InputConnection
12-10 09:24:36.814: I/Icing.InternalIcingCorporaProvider(10153): Updating corpora: A: NONE, C: DELTA
12-10 09:24:36.854: I/VS.G3EngineManager(10153): create_rm: m=GRAMMAR,l=en-US
12-10 09:24:36.854: W/Search.ConcurrentUtils(10153): Executor queue length is now 9. Perhaps some tasks are too long, or the pool is too small. [GrecoExecutor-1]
12-10 09:24:36.854: I/VS.G3EngineManager(10153): Brought up new g3 instance :/system/usr/srec/en-US/grammar.config for: en-USin: 9 ms
12-10 09:24:36.864: D/audio_hw_primary(189): out_set_parameters: enter: usecase(1: low-latency-playback) kvpairs: routing=4
12-10 09:24:36.864: D/audio_hw_primary(189): select_devices: out_snd_device(4: headphones) in_snd_device(0: )
12-10 09:24:36.874: D/audio_hw_primary(189): select_devices: out_snd_device(0: ) in_snd_device(18: headset-mic)
12-10 09:24:36.874: D/(189): Failed to fetch the lookup information of the device 00000008 
12-10 09:24:36.874: E/ACDB-LOADER(189): Error: ACDB AudProc vol returned = -19
12-10 09:24:38.864: I/LATENCY(10153): 0-4,45-2064,
12-10 09:24:38.874: I/AudioRouter(10153): ROUTE_NO_BLUETOOTH->ROUTE_NONE
12-10 09:24:38.874: I/MediaFocusControl(740):  AudioFocus  abandonAudioFocus() from android.media.AudioManager@4267ad58com.google.android.voicesearch.audio.AudioRouterImpl$1@42695f60
12-10 09:24:38.874: I/MicrophoneInputStream(10153): mic_close

It seems it triggers an ACTION_WEB_SEARCH event, so I tried to add it to the filter. I tried it two ways:

1. Declaring the filter in the manifest:

   <action android:name="android.intent.action.WEB_SEARCH" />
   

2. Declaring the filter programmatically:

   protected void onResume() {
       IntentFilter f = new IntentFilter(Intent.ACTION_WEB_SEARCH);
       registerReceiver(myReceiver, f);
   }
   
   private BroadcastReceiver myReceiver = new BroadcastReceiver() {
   
       @Override
       public void onReceive(Context context, Intent intent) {
           Log.d("AA", "ON RECEIVE");
       }
   };
   

None of this options work. As I said, this scenario isn’t of much importance, I can deal with it.

---

Wireless headset simple click

The Wireless headset simple click is the one opening the Voice Dialer and it’s the event I really need to capture. This is the log output:

12-10 10:41:22.014: E/bt-rfcomm(21800): PORT_DataInd, p_port:0x7507a7e8, p_data_co_callback is null
12-10 10:41:22.014: D/HeadsetStateMachine(21800): processVrEvent: state=1 mVoiceRecognitionStarted: false mWaitingforVoiceRecognition: false isInCall: false
12-10 10:41:22.014: I/ActivityManager(740): START u0 {act=android.intent.action.VOICE_COMMAND flg=0x10000000 cmp=com.google.android.googlequicksearchbox/com.google.android.voicesearch.handsfree.HandsFreeIntentActivity} from pid 21800
12-10 10:41:22.154: V/Avrcp(21800): New genId = 440, clearing = 1
12-10 10:41:22.154: D/HandsFreeIntentActivity(10153): #onStart(Intent { act=android.intent.action.VOICE_COMMAND flg=0x10800000 cmp=com.google.android.googlequicksearchbox/com.google.android.voicesearch.handsfree.HandsFreeIntentActivity })
12-10 10:41:22.154: D/HandsFreeIntentActivity(10153): Starting activity: Intent { act=android.intent.action.VOICE_COMMAND flg=0x10000000 cmp=com.google.android.googlequicksearchbox/com.google.android.voicesearch.handsfree.HandsFreeActivity }
12-10 10:41:22.154: I/ActivityManager(740): START u0 {act=android.intent.action.VOICE_COMMAND flg=0x10000000 cmp=com.google.android.googlequicksearchbox/com.google.android.voicesearch.handsfree.HandsFreeActivity} from pid 10153
12-10 10:41:22.204: D/OpenGLRenderer(10153): Enabling debug mode 0
12-10 10:41:22.214: W/IInputConnectionWrapper(18895): showStatusIcon on inactive InputConnection
12-10 10:41:22.244: I/ActivityManager(740): Displayed com.google.android.googlequicksearchbox/com.google.android.voicesearch.handsfree.HandsFreeActivity: +80ms (total +89ms)
12-10 10:41:22.374: I/AudioRouter(10153): ROUTE_NONE->ROUTE_BLUETOOTH_WANTED
12-10 10:41:22.384: I/MediaFocusControl(740):  AudioFocus  requestAudioFocus() from android.media.AudioManager@4267ad58com.google.android.voicesearch.audio.AudioRouterImpl$1@42695f60
12-10 10:41:22.384: V/Avrcp(21800): New genId = 441, clearing = 1
12-10 10:41:22.384: D/BluetoothManagerService(740): Message: 30
12-10 10:41:22.384: D/BluetoothHeadset(10153): Proxy object connected
12-10 10:41:22.384: I/BluetoothController(10153): BT device connected
12-10 10:41:22.394: I/AudioRouter(10153): BT required, starting SCO
12-10 10:41:22.394: I/BluetoothController(10153): Starting VR
12-10 10:41:22.394: D/BluetoothHeadset(10153): startVoiceRecognition()
12-10 10:41:22.394: D/HeadsetStateMachine(21800): Voice recognition started successfully
12-10 10:41:22.394: D/HeadsetStateMachine(21800): Initiating audio connection for Voice Recognition
12-10 10:41:22.394: W/bt-btm(21800): BTM Remote does not support 3-EDR eSCO
12-10 10:41:22.434: I/TextToSpeech(10153): Sucessfully bound to com.google.android.tts
12-10 10:41:22.454: I/TextToSpeech(10153): Connected to ComponentInfo{com.google.android.tts/com.google.android.tts.service.GoogleTTSService}
12-10 10:41:22.454: I/TextToSpeech(10153): Set up connection to ComponentInfo{com.google.android.tts/com.google.android.tts.service.GoogleTTSService}
12-10 10:41:22.484: D/dalvikvm(21966): GC_CONCURRENT freed 346K, 3% free 16647K/17064K, paused 2ms+3ms, total 13ms
12-10 10:41:22.764: D/audio_hw_primary(189): out_set_parameters: enter: usecase(1: low-latency-playback) kvpairs: routing=32
12-10 10:41:22.774: D/audio_hw_primary(189): select_devices: out_snd_device(11: bt-sco-headset) in_snd_device(0: )
12-10 10:41:24.874: I/EventLogService(1148): Aggregate from 1386666683008 (log), 1386666683008 (data)
12-10 10:41:24.994: I/ServiceDumpSys(1148): dumping service [account]
12-10 10:41:25.994: D/dalvikvm(10153): GC_CONCURRENT freed 1582K, 15% free 23868K/27920K, paused 5ms+7ms, total 60ms
12-10 10:41:26.014: I/VS.G3EngineManager(10153): create_rm: m=GRAMMAR,l=en-US
12-10 10:41:26.024: I/VS.G3EngineManager(10153): Brought up new g3 instance :/system/usr/srec/en-US/grammar.config for: en-USin: 4 ms
12-10 10:41:26.024: D/audio_hw_primary(189): out_set_parameters: enter: usecase(1: low-latency-playback) kvpairs: routing=32
12-10 10:41:26.034: D/audio_hw_primary(189): select_devices: out_snd_device(0: ) in_snd_device(25: bt-sco-mic)
12-10 10:41:26.034: D/(189): Failed to fetch the lookup information of the device 00000015 
12-10 10:41:26.034: E/ACDB-LOADER(189): Error: ACDB AudProc vol returned = -19

This time it seems it’s sending an ACTION_VOICE_COMMAND, so I tried to add it to the filter. I tried it two ways:

1. Declaring the filter in the manifest:

   <action android:name="android.intent.action.VOICE_COMMAND" />
   

2. Declaring the filter programmatically:

   protected void onResume() {
       IntentFilter f = new IntentFilter(Intent.ACTION_VOICE_COMMAND);
       registerReceiver(myReceiver, f);
   }
   
   private BroadcastReceiver myReceiver = new BroadcastReceiver() {
   
       @Override
       public void onReceive(Context context, Intent intent) {
           Log.d("AA", "ON RECEIVE");
       }
   };
   

Again, I’m not receiving these events, I don’t know why.

Answer 1

I finally managed to detect the events. I didn't know about this class:

http://developer.android.com/reference/android/bluetooth/BluetoothHeadset.html

Using the classes BluetoothAdapter, BluetoothHeadset and BluetoothDevice I can register a receiver using IntentFilter BluetoothHeadset.ACTION_AUDIO_STATE_CHANGED and I'm able to detect clicks on my headset.

The problem with this is that the broadcast is non-ordered, so I can't abort it. I can close the VoiceDialer activity right after it opens, but that's not what I want.

I'll keep struggling with this.

Thank you @Toaster for your efforts :)

EDIT:

Code used to detect the events:

protected BluetoothAdapter mBluetoothAdapter;
protected BluetoothHeadset mBluetoothHeadset;
protected BluetoothDevice mConnectedHeadset;
protected AudioManager mAudioManager;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

    if (mBluetoothAdapter != null)
    {

        mAudioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
        if (mAudioManager.isBluetoothScoAvailableOffCall())
        {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB)
            {
                mBluetoothAdapter.getProfileProxy(this, mHeadsetProfileListener, BluetoothProfile.HEADSET);
            }
        }
    }
}

 protected BluetoothProfile.ServiceListener mHeadsetProfileListener = new BluetoothProfile.ServiceListener()
{

    /**
     * This method is never called, even when we closeProfileProxy on onPause.
     * When or will it ever be called???
     */
    @Override
    public void onServiceDisconnected(int profile)
    {
        mBluetoothHeadset.stopVoiceRecognition(mConnectedHeadset);
        unregisterReceiver(mHeadsetBroadcastReceiver);
        mBluetoothHeadset = null;
    }

    @Override
    public void onServiceConnected(int profile, BluetoothProfile proxy)
    {
        // mBluetoothHeadset is just a head set profile, 
        // it does not represent a head set device.
        mBluetoothHeadset = (BluetoothHeadset) proxy;

        // If a head set is connected before this application starts,
        // ACTION_CONNECTION_STATE_CHANGED will not be broadcast. 
        // So we need to check for already connected head set.
        List<BluetoothDevice> devices = mBluetoothHeadset.getConnectedDevices();
        if (devices.size() > 0)
        {
            // Only one head set can be connected at a time, 
            // so the connected head set is at index 0.
            mConnectedHeadset = devices.get(0);

            String log;

            // The audio should not yet be connected at this stage.
            // But just to make sure we check.
            if (mBluetoothHeadset.isAudioConnected(mConnectedHeadset))
            {
                log = "Profile listener audio already connected"; //$NON-NLS-1$     
            }
            else
            {
                // The if statement is just for debug. So far startVoiceRecognition always 
                // returns true here. What can we do if it returns false? Perhaps the only
                // sensible thing is to inform the user.
                // Well actually, it only returns true if a call to stopVoiceRecognition is
                // call somewhere after a call to startVoiceRecognition. Otherwise, if 
                // stopVoiceRecognition is never called, then when the application is restarted
                // startVoiceRecognition always returns false whenever it is called.
                if (mBluetoothHeadset.startVoiceRecognition(mConnectedHeadset))
                {
                    log = "Profile listener startVoiceRecognition returns true"; //$NON-NLS-1$
                }
                else
                {
                    log = "Profile listener startVoiceRecognition returns false"; //$NON-NLS-1$
                }   
            }

            Log.d(TAG, log); 
        }

        // During the active life time of the app, a user may turn on and off the head set.
        // So register for broadcast of connection states.
        registerReceiver(mHeadsetBroadcastReceiver, 
                        new IntentFilter(BluetoothHeadset.ACTION_CONNECTION_STATE_CHANGED));

        // Calling startVoiceRecognition does not result in immediate audio connection.
        // So register for broadcast of audio connection states. This broadcast will
        // only be sent if startVoiceRecognition returns true.
        IntentFilter f = new IntentFilter(BluetoothHeadset.ACTION_AUDIO_STATE_CHANGED);
        f.setPriority(Integer.MAX_VALUE);
        registerReceiver(mHeadsetBroadcastReceiver, f);
    }
};


protected BroadcastReceiver mHeadsetBroadcastReceiver = new BroadcastReceiver()
{

    @Override
    public void onReceive(Context context, Intent intent)
    {           
        String action = intent.getAction();
        int state;
        int previousState = intent.getIntExtra(BluetoothHeadset.EXTRA_PREVIOUS_STATE, BluetoothHeadset.STATE_DISCONNECTED);
        String log = ""; 

        if (action.equals(BluetoothHeadset.ACTION_CONNECTION_STATE_CHANGED))
        {
            state = intent.getIntExtra(BluetoothHeadset.EXTRA_STATE, BluetoothHeadset.STATE_DISCONNECTED);
            if (state == BluetoothHeadset.STATE_CONNECTED)
            {
                mConnectedHeadset = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);

                // Audio should not be connected yet but just to make sure.
                if (mBluetoothHeadset.isAudioConnected(mConnectedHeadset))
                {
                    log = "Headset connected audio already connected";
                }
                else
                {

                    // Calling startVoiceRecognition always returns false here, 
                    // that why a count down timer is implemented to call
                    // startVoiceRecognition in the onTick and onFinish.
                    if (mBluetoothHeadset.startVoiceRecognition(mConnectedHeadset))
                    {
                        log = "Headset connected startVoiceRecognition returns true"; $NON-NLS-1$
                    }
                    else
                    {
                        log = "Headset connected startVoiceRecognition returns false";
                    }
                }
            }
            else if (state == BluetoothHeadset.STATE_DISCONNECTED)
            {
                // Calling stopVoiceRecognition always returns false here
                // as it should since the headset is no longer connected.
                mConnectedHeadset = null;
            }
        }
        else // audio
        {
            state = intent.getIntExtra(BluetoothHeadset.EXTRA_STATE, BluetoothHeadset.STATE_AUDIO_DISCONNECTED);

            mBluetoothHeadset.stopVoiceRecognition(mConnectedHeadset);

            if (state == BluetoothHeadset.STATE_AUDIO_CONNECTED)
            {
                log = "Head set audio connected, cancel countdown timer";  
            }
            else if (state == BluetoothHeadset.STATE_AUDIO_DISCONNECTED)
            {
                // The headset audio is disconnected, but calling
                // stopVoiceRecognition always returns true here.
                boolean returnValue = mBluetoothHeadset.stopVoiceRecognition(mConnectedHeadset);
                log = "Audio disconnected stopVoiceRecognition return " + returnValue; 
            }
        }   

        log += "\nAction = " + action + "\nState = " + state 
                + " previous state = " + previousState; 
        Log.d(TAG, log);

    }
};

Like I said, I can detect the events, but I can't aboard the broadcast.

Answer 2

For the Voice Dialer action, add the following to your manifest:

<action android:name="android.intent.action.VOICE_COMMAND" />
<category android:name="android.intent.category.DEFAULT" />

As you deduced from your debug logs, ACTION_VOICE_COMMAND is the triggered action, but without CATEGORY_DEFAULT, your app will not be considered. (I tested this with my own bluetooth headset, and it worked for me!)