How to poll available TTS engines for available languages without instantiating each one and wating for init

Question

I need to instantiate a TextToSpeech object and set a given language (which is set programmatically and may vary). I know I can use setLanguage() but that will only work if

Answer 1

Here is the setup I use for debugging - You could use elements of it in production:

// Container Class

public class ContainerVoiceEngine {

    private String label;
    private String packageName;
    private ArrayList voices;
    private Intent intent;

    public ContainerVoiceEngine() {

    }

    public ContainerVoiceEngine(final String label, final String packageName, final ArrayList voices, final Intent intent) {

        this.label = label;
        this.packageName = packageName;
        this.voices = voices;
        this.intent = intent;
    }

    public Intent getIntent() {
        return intent;
    }

    public void setIntent(final Intent intent) {
        this.intent = intent;
    }

    public String getLabel() {
        return label;
    }

    public void setLabel(final String label) {
        this.label = label;
    }

    public String getPackageName() {
        return packageName;
    }

    public void setPackageName(final String packageName) {
        this.packageName = packageName;
    }

    public ArrayList getVoices() {
        return voices;
    }

    public void setVoices(final ArrayList voices) {
        this.voices = voices;
    }
}


// Usage within an Activity - Debugging only!

  private ArrayList containerVEArray;
    private int requestCount;

    private void getEngines() {

        requestCount = 0;

        final Intent ttsIntent = new Intent();
        ttsIntent.setAction(TextToSpeech.Engine.ACTION_CHECK_TTS_DATA);

        final PackageManager pm = getPackageManager();

        final List list = pm.queryIntentActivities(ttsIntent, PackageManager.GET_META_DATA);

        containerVEArray = new ArrayList(list.size());

        for (int i = 0; i < list.size(); i++) {

            final ContainerVoiceEngine cve = new ContainerVoiceEngine();

            cve.setLabel(list.get(i).loadLabel(pm).toString());
            cve.setPackageName(list.get(i).activityInfo.applicationInfo.packageName);

            final Intent getIntent = new Intent();
            getIntent.setAction(TextToSpeech.Engine.ACTION_CHECK_TTS_DATA);

            getIntent.setPackage(cve.getPackageName());
            getIntent.getStringArrayListExtra(TextToSpeech.Engine.EXTRA_AVAILABLE_VOICES);
            getIntent.getStringArrayListExtra(TextToSpeech.Engine.EXTRA_UNAVAILABLE_VOICES);

            cve.setIntent(getIntent);

            containerVEArray.add(cve);
        }

        Log.d("TAG", "containerVEArray: " + containerVEArray.size());

        for (int i = 0; i < containerVEArray.size(); i++) {
            startActivityForResult(containerVEArray.get(i).getIntent(), i);
        }

    }

    @Override
    public void onActivityResult(final int requestCode, final int resultCode, final Intent data) {
        Log.i("TAG", "onActivityResult: requestCount: " + " - requestCode: " + requestCode);

        requestCount++;

        try {

            if (data != null) {

                final Bundle bundle = data.getExtras();

                if (bundle != null) {

                    Log.d("TAG", containerVEArray.get(requestCode).getLabel() + " - Bundle Data");

                    final Set keys = bundle.keySet();
                    final Iterator it = keys.iterator();

                    while (it.hasNext()) {
                        final String key = it.next();
                        Log.d("TAG", "Key: " + key + " = " + bundle.get(key));
                    }

                }

                if (data.hasExtra("availableVoices")) {
                    containerVEArray.get(requestCode).setVoices(data.getStringArrayListExtra("availableVoices"));
                } else {
                    containerVEArray.get(requestCode).setVoices(new ArrayList());
                }
            }

            if (requestCount == containerVEArray.size()) {

                for (int i = 0; i < containerVEArray.size(); i++) {

                    Log.v("TAG", "cve: " + containerVEArray.get(i).getLabel() + " - "
                            + containerVEArray.get(i).getVoices().size() + " - " + containerVEArray.get(i).getVoices().toString());
                }
            }

        } catch (final IndexOutOfBoundsException e) {
            Log.e("TAG", "IndexOutOfBoundsException");
            e.printStackTrace();
        } catch (final NullPointerException e) {
            Log.e("TAG", "NullPointerException");
            e.printStackTrace();
        } catch (final Exception e) {
            Log.e("TAG", "Exception");
            e.printStackTrace();
        }
    }

Hope that helps.

Edit

Further to your comment, these 'voices' are in actual fact the languages, in the sense that they return a representative Locale in their structure. Be aware though, the Locale is in a different format to the System Locale, which is really annoying and needs to be sorted in a future Android update.

Take a look at my answer here regarding the pitfalls with using tts.setLanguage(Locale). The question also deals with creating a Locale - Locale loc = new Locale(String).

You can use a loop for the ArrayList of available languages to try and construct a Locale from each, for each Engine.

Hope that helps.