How to gracefully shutdown Android Service running a speech RecognizerIntent?

Question

I have implemented a version of the SilentVoiceRecognitionService.

However, I have an issue with the Service not being shutdown properly to the extent that the next time the application is started, the service throws a ERROR_RECOGNIZER_BUSY.

In case it helps, this is how my service is declated in the Manifest:

    <service
        android:name="com.xyz.SilentVoiceRecognitionService"
        android:label="@string/app_name">
    </service>  

The SilentVoiceRecognitionService is started from the application main service (in onStartCommand):

    public int onStartCommand(Intent intent, int flags, int startId) {
    if (mLiveCard == null) {

        [...]

        startService(new Intent(this, SilentVoiceRecognitionService.class));
    }
    return START_STICKY;
}

That service is started once. Here's it declaration in the Manifest file:

    <service
        android:name="com.xyz.XYZService"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:enabled="true"
        android:exported="true">
        <intent-filter>
            <action android:name="com.google.android.glass.action.VOICE_TRIGGER" />
        </intent-filter>
        <meta-data
            android:name="com.google.android.glass.VoiceTrigger"
            android:resource="@xml/voice_trigger_start" />
    </service>

Does anyone have an idea why this SilentVoiceRecognitionService is not shutdown properly?

Answer 1

I am still not sure why there is a recognizer already listening when launching the app. However, testing for its state in onError(), cancelling the recognizer and restarting listening did work for me.

Here's the code I used:

        @Override
    public void onError(int arg0) {
         String mError = "";
            switch (arg0) {
            case SpeechRecognizer.ERROR_NETWORK_TIMEOUT:                
                mError = " network timeout"; 
                break;
            case SpeechRecognizer.ERROR_NETWORK: 
                mError = " network" ;
                return;
            case SpeechRecognizer.ERROR_AUDIO: 
                mError = " audio"; 
                break;
            case SpeechRecognizer.ERROR_SERVER: 
                mError = " server"; 
                break;
            case SpeechRecognizer.ERROR_CLIENT: 
                mError = " client"; 
                break;
            case SpeechRecognizer.ERROR_SPEECH_TIMEOUT: 
                mError = " speech time out" ; 
                break;
            case SpeechRecognizer.ERROR_NO_MATCH: 
                mError = " no match" ; 
                break;
            case SpeechRecognizer.ERROR_RECOGNIZER_BUSY: 
                mError = " recogniser busy" ; 
                mSpeechRecognizer.cancel();
                break;
            case SpeechRecognizer.ERROR_INSUFFICIENT_PERMISSIONS: 
                mError = " insufficient permissions" ; 
                break;
            default:
                mError = "Unknown Error";
            }
            Log.i(TAG,  "Error: " +  arg0 + " - " + mError);
            mSpeechRecognizer.startListening(mSpeechRecognizerIntent);
    }

Answer 2

Maybe try putting a stopService in your onDestroy of your service/activity.