Wykrywanie, czy zestaw słuchawkowy jest podłączony do urządzenia z systemem Android, czy nie.

Możesz użyć odbiornika.

<receiver android:name="com.juno.brheadset.HeadsetStateReceiver">
    <intent-filter>
        <action android:name="android.intent.action.HEADSET_PLUG"/>
    </intent-filter>
</receiver>-->

public class BRHeadsetActivity extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    IntentFilter receiverFilter = new IntentFilter(Intent.ACTION_HEADSET_PLUG);
    HeadsetStateReceiver receiver = new HeadsetStateReceiver();
    registerReceiver( receiver, receiverFilter );


}

To jest część " HeadsetObserver.java", Android SDK Source.

private final void sendIntent(int headset, int headsetState, int prevHeadsetState, String headsetName) {
    if ((headsetState & headset) != (prevHeadsetState & headset)) {
        //  Pack up the values and broadcast them to everyone
        Intent intent = new Intent(Intent.ACTION_HEADSET_PLUG);

        **intent.addFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY);**

        int state = 0;
        int microphone = 0;

        if ((headset & HEADSETS_WITH_MIC) != 0) {
            microphone = 1;
        }
        if ((headsetState & headset) != 0) {
            state = 1;
        }
        intent.putExtra("state", state);
        intent.putExtra("name", headsetName);
        intent.putExtra("microphone", microphone);

        if (LOG) Slog.v(TAG, "Intent.ACTION_HEADSET_PLUG: state: "+state+" name: "+headsetName+" mic: "+microphone);
        // TODO: Should we require a permission?
        ActivityManagerNative.broadcastStickyIntent(intent, null);
    }
}

AudioManager.isWiredHeadsetOn() zawsze zwracaj false, ponieważ wymaga uprawnień użytkownika MODIFY_AUDIO_SETTINGS.

To powinno ci pomóc: http://developer.android.com/reference/android/content/Intent.html#ACTION_HEADSET_PLUG