Android RecognitionListener onResults（）方法执行两次，为什么？

Question

这是SpeechRecgnizer的简单实现，但是onResults方法中存在的Toast会显示两次。我知道可以使用一些布尔标志来解决，但是为什么onResults方法执行两次？

speech.startListening（speechIntent）仅被调用一次一次，而onResults被执行两次。

https://developer.android.com/reference/android/speech/RecognitionListener的文档中未提及类似内容>

public class MainActivity extends AppCompatActivity implements RecognitionListener{
    Button micButton;
    SpeechRecognizer speech;
    int flag=1;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        speech = SpeechRecognizer.createSpeechRecognizer(this);
        speech.setRecognitionListener(this);
        micButton=findViewById(R.id.mic_button);
        final Intent speechIntent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
        speechIntent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL, RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
        speechIntent.putExtra(RecognizerIntent.EXTRA_LANGUAGE, "en");
        speechIntent.putExtra(RecognizerIntent.EXTRA_CALLING_PACKAGE,MainActivity.this.getPackageName());

        micButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                   speech.startListening(speechIntent);
                   Toast.makeText(MainActivity.this, "Listening", Toast.LENGTH_SHORT).show();
            }
        });
    }

    @Override
    public void onReadyForSpeech(Bundle params) {

    }

    @Override
    public void onBeginningOfSpeech() {

    }

    @Override
    public void onRmsChanged(float rmsdB) {

    }

    @Override
    public void onBufferReceived(byte[] buffer) {

    }

    @Override
    public void onEndOfSpeech() {

    }

    @Override
    public void onError(int error) {

    }

    @Override
    public void onResults(Bundle results) {
        ArrayList<String> output = results.getStringArrayList(SpeechRecognizer.RESULTS_RECOGNITION);
        Toast.makeText(this, output.toString(), Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onPartialResults(Bundle partialResults) {

    }

    @Override
    public void onEvent(int eventType, Bundle params) {

    }
}

这是SpeechRecgnizer的简单实现，但是onResults方法中存在的Toast会显示两次。我知道可以使用一些布尔标志来解决，但是为什么onResults方法会得到...

Answer 1

这是一个已知问题...........................https://issuetracker.google.com/issues/152628934