Question

您好我是Java的新手，我想知道当我已经转移到新活动时如何从另一个活动调用void方法。例如，我想打电话

onCreate（Bundle state）

来自PocketSphinxActivty.java的

在我的新活动SMSReaderMain.java

中

我已经尝试了

PocketSphinxActivity ps = new PocketSphinxActivity();
ps.onCreate(null);

它没有错误，但是当SMSReaderMain.java活动开始时它突然强制关闭而在实际设备中没有响应。

我也尝试更改为ps.onCreate(this)或ps.onCreate(SMSReaderMain.this)，但它会提供

PocketSphinxActivity类型中的方法setupRecognizer（File）不适用于参数（SMSReaderMain）

这里是完整的代码，我想在我的新活动中调用几乎所有方法SMSReaderMain.java

PocketSphinxActivity.java

package edu.cmu.pocketsphinx.demo;

public class PocketSphinxActivity extends Activity implements
    RecognitionListener {

//keyword yang digunakan dalem program untuk set ke even2 tertentu
private static final String KWS_SEARCH = "wakeup";
private static final String FORECAST_SEARCH = "forecast";
private static final String DIGITS_SEARCH = "drive mode";
private static final String MENU_SEARCH = "menu";
private static final String KEYPHRASE = "ok";

private SpeechRecognizer recognizer;
private HashMap<String, Integer> captions;



@Override
public void onCreate(Bundle state) {
    super.onCreate(state);

    // Buat nyiapin User Interface
    captions = new HashMap<String, Integer>();
    captions.put(KWS_SEARCH, R.string.kws_caption);
    captions.put(MENU_SEARCH, R.string.menu_caption);
    //captions.put(DIGITS_SEARCH, R.string.digits_caption);
    captions.put(FORECAST_SEARCH, R.string.forecast_caption);
    setContentView(R.layout.main);
    ((TextView) findViewById(R.id.caption_text))
            .setText("Preparing the recognizer");

    // Recognizer initialization is a time-consuming and it involves IO,
    // so we execute it in async task

    new AsyncTask<Void, Void, Exception>() {
        @Override
        protected Exception doInBackground(Void... params) {
            try {
                Assets assets = new Assets(PocketSphinxActivity.this);
                File assetDir = assets.syncAssets();
                setupRecognizer(assetDir);
            } catch (IOException e) {
                return e;
            }
            return null;
        }

        @Override
        protected void onPostExecute(Exception result) {
            if (result != null) {
                ((TextView) findViewById(R.id.caption_text))
                        .setText("Failed to init recognizer " + result);
            } else {
                switchSearch(KWS_SEARCH);
            }
        }
    }.execute();
}

//nyocokin keyword dan pindah2 menu
@Override
public void onPartialResult(Hypothesis hypothesis) {
    String text = hypothesis.getHypstr();
    try {
    Intent i= null;
    if (text.equals(KEYPHRASE)) {
        switchSearch(MENU_SEARCH);
    }
    if (text.equals(DIGITS_SEARCH)) {
        //panggil class SMSReaderMain
        recognizer.stop();
        i = new Intent(getApplicationContext(),SMSReaderMain.class);
        startActivity(i);
    }
    if (text.equals(FORECAST_SEARCH)) {
        switchSearch(FORECAST_SEARCH);
    }
   //else
        //((TextView) findViewById(R.id.result_text)).setText(text);
} catch (Exception e) {
    e.printStackTrace();
}
}

//nge pop up keyword yang sesuai kita ucapin sama library yg udah ada 
@Override
public void onResult(Hypothesis hypothesis) {
    ((TextView) findViewById(R.id.result_text)).setText("");
    if (hypothesis != null) {
        String text = hypothesis.getHypstr();
        makeText(getApplicationContext(), text, Toast.LENGTH_SHORT).show();
    }
}

@Override
public void onBeginningOfSpeech() {
}

//kembali ke menu utama
/*@Override
public void onEndOfSpeech() {
    if (DIGITS_SEARCH.equals(recognizer.getSearchName())
            || FORECAST_SEARCH.equals(recognizer.getSearchName()))
        switchSearch(KWS_SEARCH);
}**/

//nampilin caption yg di mau sesuai dengan keyword
public void switchSearch(String searchName) {
    recognizer.stop();
    recognizer.startListening(searchName);
    String caption = getResources().getString(captions.get(searchName));
    ((TextView) findViewById(R.id.caption_text)).setText(caption);
}

//inisiasi recognizer di awal
public void setupRecognizer(File assetsDir) {
    File modelsDir = new File(assetsDir, "models");
    recognizer = defaultSetup()
            .setAcousticModel(new File(modelsDir, "hmm/en-us-semi"))
            .setDictionary(new File(modelsDir, "dict/cmu07a.dic"))
            .setRawLogDir(assetsDir).setKeywordThreshold(1e-20f)
            .getRecognizer();
    recognizer.addListener(this);

    // Create keyword-activation search.
    recognizer.addKeyphraseSearch(KWS_SEARCH, KEYPHRASE);

    // Create grammar-based searches.
    File menuGrammar = new File(modelsDir, "grammar/mulai.gram");
    recognizer.addGrammarSearch(MENU_SEARCH, menuGrammar);
    //File digitsGrammar = new File(modelsDir, "grammar/digits.gram");
    //recognizer.addGrammarSearch(DIGITS_SEARCH, digitsGrammar);

    // Create language model search.
    File languageModel = new File(modelsDir, "lm/weather.dmp");
    recognizer.addNgramSearch(FORECAST_SEARCH, languageModel);
}

@Override
public void onEndOfSpeech() {
    // TODO Auto-generated method stub

}
}

SMSReaderMAin.java

public class SMSReaderMain extends Activity {   

private final int CHECK_CODE = 0x1; 
private final int LONG_DURATION = 5000;
private final int SHORT_DURATION = 1200;

private Speaker speaker;    

private ToggleButton toggle;
private OnCheckedChangeListener toggleListener;

private TextView smsText;
private TextView smsSender; 
private BroadcastReceiver smsReceiver;




@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    //PocketSphinxActivity ps = new PocketSphinxActivity();
    //ps.setupRecognizer(null);
    //ps.onPartialResult(null);
    //ps.onResult(null);
    //ps.switchSearch(null);

    setContentView(R.layout.main_sms);          

    //recognizer.startListening(searchName);

    toggle = (ToggleButton)findViewById(R.id.speechToggle);
    smsText = (TextView)findViewById(R.id.sms_text);
    smsSender = (TextView)findViewById(R.id.sms_sender);

    toggleListener = new OnCheckedChangeListener() {            
        @Override
        public void onCheckedChanged(CompoundButton view, boolean isChecked) {
            if(isChecked){
                speaker.allow(true);
                speaker.speak(getString(R.string.start_speaking));
            }else{
                speaker.speak(getString(R.string.stop_speaking));
                speaker.allow(false);                   
            }
        }
    };      
    toggle.setOnCheckedChangeListener(toggleListener);

    checkTTS();
    initializeSMSReceiver();
    registerSMSReceiver();
}   

private void checkTTS(){
    Intent check = new Intent();
    check.setAction(TextToSpeech.Engine.ACTION_CHECK_TTS_DATA);
    startActivityForResult(check, CHECK_CODE);
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if(requestCode == CHECK_CODE){
        if(resultCode == TextToSpeech.Engine.CHECK_VOICE_DATA_PASS){
            speaker = new Speaker(this);
        }else {
            Intent install = new Intent();
            install.setAction(TextToSpeech.Engine.ACTION_INSTALL_TTS_DATA);
            startActivity(install);
        }
    }
}

private void initializeSMSReceiver(){
    smsReceiver = new BroadcastReceiver(){
        @Override
        public void onReceive(Context context, Intent intent) {

            Bundle bundle = intent.getExtras();
            if(bundle!=null){
                Object[] pdus = (Object[])bundle.get("pdus");
                for(int i=0;i<pdus.length;i++){
                    byte[] pdu = (byte[])pdus[i];
                    SmsMessage message = SmsMessage.createFromPdu(pdu);
                    String text = message.getDisplayMessageBody();
                    String sender = getContactName(message.getOriginatingAddress());
                    speaker.pause(LONG_DURATION);
                    speaker.speak("You have a new message from" + sender + "!");
                    speaker.pause(SHORT_DURATION);
                    speaker.speak(text);
                    smsSender.setText("Message from " + sender);
                    smsText.setText(text);
                }
            }

        }           
    };      
}

private void registerSMSReceiver() {    
    IntentFilter intentFilter = new IntentFilter("android.provider.Telephony.SMS_RECEIVED");
    registerReceiver(smsReceiver, intentFilter);
}

private String getContactName(String phone){
    Uri uri = Uri.withAppendedPath(PhoneLookup.CONTENT_FILTER_URI, Uri.encode(phone));
    String projection[] = new String[]{ContactsContract.Data.DISPLAY_NAME};
    Cursor cursor = getContentResolver().query(uri, projection, null, null, null);              
    if(cursor.moveToFirst()){
        return cursor.getString(0);
    }else {
        return "unknown number";
    }
}

@Override
protected void onDestroy() {    
    super.onDestroy();
    unregisterReceiver(smsReceiver);
    speaker.destroy();
 }

}

Answer 1

对于Android中的编程方式，这是一种非常错误的方法。活动是由Android直接管理的Android应用程序中的主要核心组件之一，这意味着系统创建它们并由操作系统管理。 onCreate方法是生命周期的一部分，它由系统自动调用。 Here您拥有活动的生命周期。

开始新活动的方式是：

Intent intent = new Intent(mContext, MyActivity.class);
startActivity(intent);

由于活动是由系统实现的，因此您无法直接调用其上的方法。活动之间的通信方式是在intent中提供bundle对象，因此在新的Activity中，您可以从以下位置获取数据：

getIntent().getExtras()

您还可以使用startActivityForResult代替startActivity提供反向信息，并在onActivityResult中收到结果。

您拥有所需的信息here。

Answer 2

活动对应于您要在屏幕上显示的内容。如果您不打算显示任何内容，请不要创建活动。

在此示例中，您根本不需要PocketsphinxActivity。您可以将PocketsphinxActivity的所有方法移至SMSReaderMain活动中。

如果您想将语音识别代码分成单独的类，则可以创建单独的PocketsphinxRecognizer类，但是从Object继承，而不是从Activity继承。

调用具有来自其他活动的值的“void”方法

2 个答案: