添加 TTS 代码时 Android 应用程序崩溃

Question

我是 Android 开发的新手，我正在尝试在（android 4.4 平台和三星 Galaxy S4）上运行基本的文本转语音 (TTS) 代码，但应用程序一旦打开就会崩溃。给出了主要活动代码和系统消息的捕获屏幕。

package com.example.ttscode;

import java.util.Locale;

import android.app.Activity;
import android.os.Bundle;
import android.speech.tts.TextToSpeech;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class MainActivity extends Activity implements
    TextToSpeech.OnInitListener {
/** Called when the activity is first created. */

private TextToSpeech tts;
private Button btnSpeak;
private EditText txtText;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    tts = new TextToSpeech(this, this);

    btnSpeak = (Button) findViewById(R.id.action_settings);

    txtText = (EditText) findViewById(R.id.action_settings);

    // button on click event
    btnSpeak.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View arg0) {
            speakOut();
        }

    });
}

@Override
public void onDestroy() {
    // Don't forget to shutdown tts!
    if (tts != null) {
        tts.stop();
        tts.shutdown();
    }
    super.onDestroy();
}

@Override
public void onInit(int status) {

    if (status == TextToSpeech.SUCCESS) {

        int result = tts.setLanguage(Locale.US);

        if (result == TextToSpeech.LANG_MISSING_DATA
                || result == TextToSpeech.LANG_NOT_SUPPORTED) {
            Log.e("TTS", "This Language is not supported");
        } else {
            btnSpeak.setEnabled(true);
            speakOut();
        }

    } else {
        Log.e("TTS", "Initilization Failed!");
    }

}

private void speakOut() {

    String text = txtText.getText().toString();

    tts.speak(text, TextToSpeech.QUEUE_FLUSH, null);
}
}

图片在此链接http://i.stack.imgur.com/CYvz2.jpg

这是logcat中的红色文字：

04-15 23:38:41.026：E/AndroidRuntime(32189)：致命异常：主要 04-15 23:38:41.026: E/AndroidRuntime(32189): 进程: com.example.ttscode, PID: 32189 04-15 23:38:41.026: E/AndroidRuntime(32189): java.lang.RuntimeException: 无法启动活动 ComponentInfo{com.example.ttscode/com.example.ttscode.MainActivity}: java.lang.NullPointerException 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2305) 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2363) 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 android.app.ActivityThread.access$900(ActivityThread.java:161) 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 android.app.ActivityThread$H.handleMessage(ActivityThread.java:1265) 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 android.os.Handler.dispatchMessage(Handler.java:102) 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 android.os.Looper.loop(Looper.java:157) 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 android.app.ActivityThread.main(ActivityThread.java:5356) 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 java.lang.reflect.Method.invokeNative(Native Method) 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 java.lang.reflect.Method.invoke(Method.java:515) 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1265) 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081) 04-15 23:38:41.026: E/AndroidRuntime(32189): at dalvik.system.NativeStart.main(Native Method) 04-15 23:38:41.026: E/AndroidRuntime(32189): 引起: java.lang.NullPointerException 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 com.example.ttscode.MainActivity.onCreate(MainActivity.java:33) 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 android.app.Activity.performCreate(Activity.java:5426) 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105) 04-15 23:38:41.026: E/AndroidRuntime(32189): 在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2269) 04-15 23:38:41.026: E/AndroidRuntime(32189): ... 11 更多 04-15 23:38:47.171: I/Process(32189): 发送信号。 PID：32189 SIG：9

Answer 1

Thread x;
MediaPlayer  mediaPlayer;
 x=new Thread(){    
public void run(){
         try{
             url1="http://www.translate.google.com/translate_tts?ie=UTF-8&q="this is word which is speech"%0A&tl="this is language"&prev=input";


            mediaPlayer=new MediaPlayer();
            mediaPlayer.reset();
            mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
            mediaPlayer.setDataSource(url1);
            mediaPlayer.prepare(); // might take long! (for buffering, etc)
            mediaPlayer.start();
                    } catch (IllegalArgumentException e) {
                        mediaPlayer.reset();
                    } catch (IllegalStateException e) {
                        mediaPlayer.reset();
                    } catch (IOException e) {
                        mediaPlayer.reset();
                    } 


            finally{ 
            //  x.suspend();
            } 
     }

    };

你可以这样使用：

x.start();

别忘了给予上网许可：

<uses-permission android:name="android.permission.INTERNET" />

Answer 2

您在这里使用相同的 ID 来查找两个不同的视图：

btnSpeak = (Button) findViewById(R.id.action_settings);
txtText = (EditText) findViewById(R.id.action_settings);

当您尝试将您的onClickListener 分配给btnSpeak 时，它看起来会导致NullPointerException