android - 如何在不实例化每个语言并等待初始化的情况下轮询可用的 TTS 引擎以获取可用语言

Question

我需要实例化一个 TextToSpeech 对象并设置给定的语言(以编程方式设置并且可能会有所不同)。我知道我可以使用 setLanguage() 但只有当语言在特定 TextToSpeech 实例正在使用的 TTS 引擎中可用时才有效。我知道我可以通过 myTTS.isLanguageAvailable() 检查一种语言是否可用，但这只会告诉我该语言在当前引擎上是否可用。

问题是用户可能安装了多个 TTS 引擎，其中一个可能提供了所需的语言，但默认的没有。在那种情况下，我想找到引擎，使用它并设置语言。

所以我需要遍历可用的 TTS 引擎并“询问”每个引擎是否有所需的可用语言。

我试过这个:

mUserLocale=new Locale("it-IT"); //just an example

mTextToSpeech=new TextToSpeech(getApplicationContext(), this);
if (mTextToSpeech.isLanguageAvailable(mUserLocale)<0) {

    List<TextToSpeech.EngineInfo> engines=mTextToSpeech.getEngines();
    int currentmatchquality=-1;
    String defaultTTSEngine=mTextToSpeech.getDefaultEngine();
    mTextToSpeech.shutdown();
    mTextToSpeech=null;
    for (int i=0; i<engines.size(); i++) {
        TextToSpeech.EngineInfo engineinfo=engines.get(i);
        Log.d("MainActivity", "Examining TTS engine "+engineinfo.name);
        if (engineinfo.name.equals(defaultTTSEngine)) {
            Log.d("MainActivity", "Skipping default TTS engine "+engineinfo.name);
            continue;
        }
        TextToSpeech candidateTTS=new TextToSpeech(getApplicationContext(),this,engineinfo.name);
        int matchquality=candidateTTS.isLanguageAvailable(mUserLocale);
        if (matchquality>currentmatchquality) {
            Log.d("MainActivity", "Selecting TTS engine "+engineinfo.name);
            mTextToSpeech.shutdown();
            mTextToSpeech=candidateTTS;
            mTTSEngine=engineinfo.name;
            currentmatchquality=matchquality;

        }
        else {
            Log.d("MainActivity", "   "+mUserLocale.toString()+" not available on this engine: "+matchquality);
        }
    }
    if (mTTSEngine==null) mTTSEngine=defaultTTSEngine;
    mTextToSpeech=new TextToSpeech(getApplicationContext(),this,mTTSEngine);
}

if (mTextToSpeech.isLanguageAvailable(mUserLocale)>=0) mTextToSpeech.setLanguage(mUserLocale);

问题是我系统地从 isLanguageAvailable 得到 -2:

D/MainActivity﹕ Examining TTS engine com.google.android.tts
I/TextToSpeech﹕ Sucessfully bound to com.google.android.tts
W/TextToSpeech﹕ isLanguageAvailable failed: not bound to TTS engine
D/MainActivity﹕ it-it not available on this engine: -2

我猜这是因为我需要等待 TTS 的初始化事件，然后才能查询可用语言。

那会很麻烦。有没有一种方法可以循环遍历现有的 TTS 引擎并检查它们中的每一个是否有一种语言可用(或获取每个引擎的所有可用语言的列表)而无需为每个引擎实例化 TextToSpeech 对象并等待它被初始化？

Answer 1

这是我用于调试的设置 - 您可以在生产中使用它的元素:

// Container Class

public class ContainerVoiceEngine {

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

    public ContainerVoiceEngine() {

    }

    public ContainerVoiceEngine(final String label, final String packageName, final ArrayList<String> 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<String> getVoices() {
        return voices;
    }

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


// Usage within an Activity - Debugging only!

  private ArrayList<ContainerVoiceEngine> 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<ResolveInfo> list = pm.queryIntentActivities(ttsIntent, PackageManager.GET_META_DATA);

        containerVEArray = new ArrayList<ContainerVoiceEngine>(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<String> keys = bundle.keySet();
                    final Iterator<String> 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<String>());
                }
            }

            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();
        }
    }

希望对您有所帮助。

编辑

根据您的评论，这些“声音”实际上是语言，从某种意义上说，它们在其结构中返回具有代表性的语言环境。但请注意，Locale 与 System Locale 的格式不同，这真的很烦人，需要在未来的 Android 更新中进行排序。

看看my answer here关于使用 tts.setLanguage(Locale) 的陷阱。该问题还涉及创建语言环境 - Locale loc = new Locale(String)。

您可以对可用语言的 ArrayList 使用循环，以尝试为每个引擎从每个语言构建一个 Locale。

希望对您有所帮助。