App-Absturz, wenn prinln Beschleunigungsmesser Ereigniswert

Question

Ich entwickle eine PC-Remote-Anwendung, die Cursor-Maus mit Android Beschleunigungssensor bewegen kann. Ich benutze java.io.PrintWriter, um den Beschleunigungsmesser-Ereigniswert von onSensorChanged zu lesen und an den Server zu senden, aber den Absturz der App. Bitte helfen Sie. error log Code

Context context; 
ToggleButton toggleButton2; 
private ToggleButton toggleButton1; 
Button nextButton; 
Button previousButton; 
TextView mousePad; 
TextView returnedText; 

TextView textViewX; 
TextView textViewY; 

private SensorManager mSensorManager; 
private Sensor mAccelerometer; 

private boolean isConnected=false; 
private boolean mouseMoved=false; 
private Socket socket; 
private PrintWriter out; 

private float initX =0; 
private float initY =0; 
private float disX =0; 
private float disY =0; 

private SpeechRecognizer speech = null; 
private Intent recognizerIntent; 
private String LOG_TAG = "VoiceRecognitionActivity"; 


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

    mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE); 
    mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER); 

    context = this; 
    returnedText = (TextView) findViewById(R.id.returnedText); 
    toggleButton1 = (ToggleButton) findViewById(R.id.toggleButton1); 
    toggleButton2 = (ToggleButton) findViewById(R.id.toggleButton2); 
    nextButton = (Button)findViewById(R.id.nextButton); 
    previousButton = (Button)findViewById(R.id.previousButton); 

    textViewX = (TextView) findViewById(R.id.textViewX); 
    textViewY = (TextView) findViewById(R.id.textViewy); 


    nextButton.setOnClickListener(this); 
    previousButton.setOnClickListener(this); 


    mousePad = (TextView)findViewById(R.id.mousePad); 


    mousePad.setOnTouchListener(new View.OnTouchListener() { 
     @Override 
     public boolean onTouch(View v, MotionEvent event) { 
      if(isConnected && out!=null){ 
       switch(event.getAction()){ 
        case MotionEvent.ACTION_DOWN: 
         //save X and Y positions when user touches the TextView 
         initX =event.getX(); 
         initY =event.getY(); 
         mouseMoved=false; 
         break; 
        case MotionEvent.ACTION_MOVE: 
         disX = event.getX()- initX; //Mouse movement in x direction 
         disY = event.getY()- initY; //Mouse movement in y direction 
         /*set init to new position so that continuous mouse movement 
         is captured*/ 
         initX = event.getX(); 
         initY = event.getY(); 
         if(disX !=0|| disY !=0){ 
          out.println(disX +","+ disY); //send mouse movement to server 
         } 
         mouseMoved=true; 
         break; 
        case MotionEvent.ACTION_UP: 
         //consider a tap only if usr did not move mouse after ACTION_DOWN 
         if(!mouseMoved){ 
          out.println(Constants.MOUSE_LEFT_CLICK); 
         } 
       } 
      } 
      return true; 
     } 
    }); 



    speech = SpeechRecognizer.createSpeechRecognizer(this); 
    speech.setRecognitionListener(this); 
    recognizerIntent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH); 
    recognizerIntent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_PREFERENCE, 
      "en"); 
    recognizerIntent.putExtra(RecognizerIntent.EXTRA_CALLING_PACKAGE, 
      this.getPackageName()); 
    recognizerIntent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL, 
      RecognizerIntent.LANGUAGE_MODEL_WEB_SEARCH); 
    recognizerIntent.putExtra(RecognizerIntent.EXTRA_MAX_RESULTS, 1); 

    toggleButton1.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { 

     @Override 
     public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { 
      if (isChecked) { 
       speech.startListening(recognizerIntent); 
      } else { 
       speech.stopListening(); 
      } 
     } 
    }); 
    mSensorManager.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_NORMAL); 

} 


@Override 
public boolean onCreateOptionsMenu(Menu menu) { 
    getMenuInflater().inflate(R.menu.menu_main, menu); 
    return true; 
} 

@Override 
public boolean onOptionsItemSelected(MenuItem item) { 

    int id = item.getItemId(); 
    if(id == R.id.action_settings) { 
     Intent i = new Intent(getApplicationContext(), SetIP.class); 
     startActivity(i); 
     finish(); 
    } 

    //noinspection SimplifiableIfStatement 
    if(id == R.id.action_connect) { 

     Intent intent = getIntent(); 
     String ipadd = intent.getStringExtra("ipaddress"); 
     ConnectPhoneTask connectPhoneTask = new ConnectPhoneTask(); 
     connectPhoneTask.execute(ipadd); 
     return true; 
    } 

    return super.onOptionsItemSelected(item); 
} 


@Override 
public void onClick(View v) { 
    switch (v.getId()) { 
     case R.id.playPauseButton: 
      { 
       out.println(Constants.MOUSE_RIGHT_CLICK); 
      } 
      break; 
     case R.id.nextButton: 
      if (isConnected && out!=null) { 
       out.println(Constants.NEXT); 
      } 
      break; 
     case R.id.previousButton: 
      if (isConnected && out!=null) { 
       out.println(Constants.PREVIOUS); 
      } 
      break; 
    } 

} 

@Override 
public void onDestroy() 
{ 
    super.onDestroy(); 
    if(isConnected && out!=null) { 
     try { 
      out.println("exit"); 
      socket.close(); 
     } catch (IOException e) { 
      Log.e("remotedroid", "Error in closing socket", e); 
     } 
    } 
} 

@Override 
public void onResume() { 
    super.onResume(); 
    mSensorManager.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_NORMAL); 
} 

@Override 
protected void onPause() { 
    super.onPause(); 
    if (speech != null) { 
     speech.destroy(); 
     Log.i(LOG_TAG, "destroy"); 
    } 
    mSensorManager.unregisterListener(this); 
} 

public void onStop() { 
    super.onStop(); 
    mSensorManager.unregisterListener(this); 
} 

public void onAccuracyChanged(Sensor sensor, int accuracy) { 
    // can be safely ignored for this demo 
} 

public void onSensorChanged(SensorEvent event) { 

    float x = event.values[0]; 
    float y = event.values[1]; 


    textViewX.setText(Float.toString(x)); 
    textViewY.setText(Float.toString(y)); 

    Log.i(LOG_TAG, x+","+y); 

    if ((x = null) && (y = null)) 
    try{ 
    out.println(String.valueOf(x)+","+String.valueOf(y)); 

}catch (IOException e) { 
Log.e("remotedroid", "huhuhu", e);}} 

@Override 
public void onBeginningOfSpeech() { 
    Log.i(LOG_TAG, "onBeginningOfSpeech"); 
} 

@Override 
public void onBufferReceived(byte[] buffer) { 
    Log.i(LOG_TAG, "onBufferReceived: " + buffer); 
} 

@Override 
public void onEndOfSpeech() { 
    Log.i(LOG_TAG, "onEndOfSpeech"); 
    toggleButton1.setChecked(false); 
} 

@Override 
public void onError(int errorCode) { 
    String errorMessage = getErrorText(errorCode); 
    Log.d(LOG_TAG, "FAILED " + errorMessage); 
    toggleButton1.setChecked(false); 
} 

@Override 
public void onEvent(int arg0, Bundle arg1) { 
    Log.i(LOG_TAG, "onEvent"); 
} 

@Override 
public void onPartialResults(Bundle arg0) { 
    Log.i(LOG_TAG, "onPartialResults"); 
} 

@Override 
public void onReadyForSpeech(Bundle arg0) { 
    Log.i(LOG_TAG, "onReadyForSpeech"); 
} 

@Override 
public void onResults(Bundle results) { 
    Log.i(LOG_TAG, "onResults"); 
    ArrayList<String> matches = results 
      .getStringArrayList(SpeechRecognizer.RESULTS_RECOGNITION); 
    String text = ""; 
    for (String result : matches) { 
     text = result; 
    } 

    out.println(text); 
    returnedText.setText(text); 

} 

@Override 
public void onRmsChanged(float rmsdB) { 
    Log.i(LOG_TAG, "onRmsChanged: " + rmsdB); 

} 

public static String getErrorText(int errorCode) { 
    String message; 
    switch (errorCode) { 
     case SpeechRecognizer.ERROR_AUDIO: 
      message = "Audio recording error"; 
      break; 
     case SpeechRecognizer.ERROR_CLIENT: 
      message = "Client side error"; 
      break; 
     case SpeechRecognizer.ERROR_INSUFFICIENT_PERMISSIONS: 
      message = "Insufficient permissions"; 
      break; 
     case SpeechRecognizer.ERROR_NETWORK: 
      message = "Network error"; 
      break; 
     case SpeechRecognizer.ERROR_NETWORK_TIMEOUT: 
      message = "Network timeout"; 
      break; 
     case SpeechRecognizer.ERROR_NO_MATCH: 
      message = "No match"; 
      break; 
     case SpeechRecognizer.ERROR_RECOGNIZER_BUSY: 
      message = "RecognitionService busy"; 
      break; 
     case SpeechRecognizer.ERROR_SERVER: 
      message = "error from server"; 
      break; 
     case SpeechRecognizer.ERROR_SPEECH_TIMEOUT: 
      message = "No speech input"; 
      break; 
     default: 
      message = "Didn't understand, please try again."; 
      break; 
    } 
    return message; 
} 

public class ConnectPhoneTask extends AsyncTask<String,Void,Boolean> { 

    @Override 
    protected Boolean doInBackground(String... params) { 
     boolean result = true; 
     try { 
      InetAddress serverAddr = InetAddress.getByName(params[0]); 
      socket = new Socket(serverAddr, Constants.SERVER_PORT);//Open socket on server IP and port 
     } catch (IOException e) { 
      Log.e("remotedroid", "Error while connecting", e); 
      result = false; 
     } 
     return result; 
    } 

    @Override 
    protected void onPostExecute(Boolean result) 
    { 
     isConnected = result; 
     Toast.makeText(context,isConnected?"Connected to server!":"Error while connecting",Toast.LENGTH_LONG).show(); 
     try { 
      if(isConnected) { 
       out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket 
         .getOutputStream())), true); 

      } 
     }catch (IOException e){ 
      Log.e("remotedroid", "Error while creating OutWriter", e); 
      Toast.makeText(context,"Error while connecting",Toast.LENGTH_LONG).show(); 
     } 
    } 
} 

}

Answer 1

Sicherstellen, dass der variable out eingeleitet wird, bevor es verwendet wird. Mit Blick auf den Code, verwenden

if(isConnected && out!=null) { 
    // Your code to use out 
    // out.println(.......); 
} 

Die obige if Bedingung prüft, ob die Variable nicht null ist und auch, dass die Verbindung bereits hergestellt.

In der Klasse ConnectPhoneTask ist onPostExecuted Verfahren, bei dem die out Variable ausgelöst wird, stellen Sie sicher, dass die Verbindung mit dem Telefon gemacht wird.

//This is where the variable is initiated already in your code 
out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket 
         .getOutputStream())), true); 

So ist die out Variable sollte nur einmal verwendet werden, nachdem die Verbindung hergestellt wird.

Siehe Beispiel unten

public void onSensorChanged(SensorEvent event) { 
    float x = event.values[0]; 
    float y = event.values[1]; 

    textViewX.setText(Float.toString(x)); 
    textViewY.setText(Float.toString(y)); 

    Log.i(LOG_TAG, x+","+y); 

    if(isConnected && out!=null) 
     out.println(String.valueOf(x) + "," + String.valueOf(y)); 
}