语音搜索/语音识别器在快速启动/停止收听时崩溃

Question

我有一个使用 SpeechRecognizer 的应用（在 onCreate 函数中）：

mIntent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
mIntent.putExtra(RecognizerIntent.EXTRA_CALLING_PACKAGE, this.getPackageName());
mRecognizer = SpeechRecognizer.createSpeechRecognizer(this);
mRecognizer.setRecognitionListener(this);

我有一个启动和停止语音识别的按钮（在 onClick 中）：

if (view.getId() == R.id.btnSpeak) {
    if (mIsRecording) {
        mRecognizer.stopListening();
        mBtnSpeak.setBackgroundResource(R.drawable.mic);
        mIsCanceled = true;

    } else {
        mRecognizer.startListening(mIntent);
        mBtnSpeak.setBackgroundResource(R.drawable.mic_green);
    }

    mIsRecording = !mIsRecording;
}

问题是，当我在活动开始时快速点击按钮时，会出现强制关闭通知，并显示以下错误日志：

05-28 11:35:19.460: E/AndroidRuntime(9288): FATAL EXCEPTION: main
05-28 11:35:19.460: E/AndroidRuntime(9288): java.lang.NullPointerException
05-28 11:35:19.460: E/AndroidRuntime(9288):     at com.google.android.voicesearch.speechservice.MicrophoneManagerImpl.stopListening(MicrophoneManagerImpl.java:195)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at com.google.android.voicesearch.speechservice.RecognitionControllerImpl.onStopListening(RecognitionControllerImpl.java:280)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at com.google.android.voicesearch.GoogleRecognitionService.onStopListening(GoogleRecognitionService.java:58)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at android.speech.RecognitionService.dispatchStopListening(RecognitionService.java:118)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at android.speech.RecognitionService.access$100(RecognitionService.java:36)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at android.speech.RecognitionService$1.handleMessage(RecognitionService.java:82)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at android.os.Handler.dispatchMessage(Handler.java:99)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at android.os.Looper.loop(Looper.java:130)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at android.app.ActivityThread.main(ActivityThread.java:3746)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at java.lang.reflect.Method.invokeNative(Native Method)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at java.lang.reflect.Method.invoke(Method.java:507)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:895)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:653)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at dalvik.system.NativeStart.main(Native Method)
05-28 11:35:19.460: E/AndroidRuntime(9288): [Blue Error Handler] Make Debugging Report file for main
05-28 11:35:19.460: E/AndroidRuntime(9288): java.lang.NullPointerException
05-28 11:35:19.460: E/AndroidRuntime(9288):     at com.google.android.voicesearch.speechservice.MicrophoneManagerImpl.stopListening(MicrophoneManagerImpl.java:195)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at com.google.android.voicesearch.speechservice.RecognitionControllerImpl.onStopListening(RecognitionControllerImpl.java:280)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at com.google.android.voicesearch.GoogleRecognitionService.onStopListening(GoogleRecognitionService.java:58)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at android.speech.RecognitionService.dispatchStopListening(RecognitionService.java:118)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at android.speech.RecognitionService.access$100(RecognitionService.java:36)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at android.speech.RecognitionService$1.handleMessage(RecognitionService.java:82)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at android.os.Handler.dispatchMessage(Handler.java:99)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at android.os.Looper.loop(Looper.java:130)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at android.app.ActivityThread.main(ActivityThread.java:3746)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at java.lang.reflect.Method.invokeNative(Native Method)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at java.lang.reflect.Method.invoke(Method.java:507)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:895)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:653)
05-28 11:35:19.460: E/AndroidRuntime(9288):     at dalvik.system.NativeStart.main(Native Method)

它不会使应用程序崩溃，但我想防止这种情况发生。根据我从日志中了解到的情况，我的代码在语音识别器准备好之前称为停止侦听。有没有办法检查是否可以停止监听/开始监听？

此外，只有当我在活动开始时快速点击它时才会出现该错误。否则，speechrecognizer 只会调用 onError，我可以从那里更新我的按钮。我正在考虑添加一个延迟，让语音识别器有时间处理事情，但感觉很笨拙。

Answer 1

你应该打电话给mRecognizer.cancel();而不是mRecognizer.stopListening();
如果操作系统是 JB，您必须实现倒数计时器，请参阅 Android Speech Recognition as a service on Android 4.1 & 4.2

Answer 2

你不能完全用取消代替停止并说它解决了快速停止问题，因为取消不一样 -

cancel 将停止识别器并且不显示任何结果。
stopListening 将停止录制并触发 onResults 侦听器回调，并转录到目前为止的录制内容。

在我的手机上 (OS 4.4.2) - 我发现在onReadyForSpeech 发生之前调用stopListening 会导致识别器卡住！未调用 onResults 或 onError 并尝试再次启动它会导致 BUSY 错误。

解决方案 - 仅在 onReadyForSpeech 上将 mIsRecording 设置为 true

当您想要停止识别器调用stopListening 时，仅当标志为真时。如果为 false，则改为调用 cancel 并手动触发结束事件。