java - 文本到语音 android 在 Activity 可见时输出语音

Question

我正在为视障人士构建一个 Android native 应用程序，并且我想使用 android TTS - android.speech.tts.TextToSpeech 来引导用户使用我的应用程序。我在单击按钮后成功显示了语音，但我也想在 Activity 可见后输出欢迎消息。这是一个代码 fragment :

public class MainActivity extends AppCompatActivity  {
    private TextToSpeech textToSpeech;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        textToSpeech=new TextToSpeech(this, new TextToSpeech.OnInitListener() {
            @Override
            public void onInit(int status) {
                if (status==TextToSpeech.SUCCESS){
                    int result=textToSpeech.setLanguage(Locale.getDefault());
                    if (result == TextToSpeech.LANG_MISSING_DATA
                            || result == TextToSpeech.LANG_NOT_SUPPORTED) {
                        Log.e("TTS", "Language not supported");
                    } else {
                        Log.d("TTS","Speech initialized");
                    }
                } else {
                    Log.e("TTS", "Initialization failed");
                }
            }
        });
        speak("welcome");
        speak("Click on the button to begin settings ");

        audio.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View v){
                speak("this is a test");
            }
        });
    }
    public void speak(final String S){
    textToSpeech.speak(S,TextToSpeech.QUEUE_ADD,null);
    }
}

Answer 1

问题是 tts 尚未初始化。

解决这个问题的最快方法就是将介绍性的发言命令移到 onInit 中:

@Override
            public void onInit(int status) {
                if (status==TextToSpeech.SUCCESS){
                    int result=textToSpeech.setLanguage(Locale.getDefault());
                    if (result == TextToSpeech.LANG_MISSING_DATA
                            || result == TextToSpeech.LANG_NOT_SUPPORTED) {
                        Log.e("TTS", "Language not supported");
                    } else {
                        Log.d("TTS","Speech initialized");

                        speak("welcome");
                        speak("Click on the button to begin settings ");
                    }
                } else {
                    Log.e("TTS", "Initialization failed");
                }
            }