Android-выход из системы Facebook Сбой

Question

Я скопировал код выхода из учебника Android android. Каждый раз, когда я пытаюсь выйти из системы, я получаю исключение нулевого указателя.

Вот код ...

private AsyncFacebookRunner mAsyncRunner; 

...

   mAsyncRunner.logout(home.this, new RequestListener() { 
       @Override 
       public void onComplete(String response, Object state) 
       { 
       /* mPrefs.edit().putBoolean("firstTime", true).commit(); 
        userName.setText("Logged out!");*/ 
       } 

       @Override 
       public void onIOException(IOException e, Object state) { 
        Log.d("IOExcenption", e.toString()); 
       } 

       @Override 
       public void onFileNotFoundException(FileNotFoundException e, 
        Object state) { 
        Log.d("FileNotFoundException", e.toString()); 
       } 

       @Override 
       public void onMalformedURLException(MalformedURLException e, 
        Object state) { 
        Log.d("MalformedUrlExpection", e.toString()); 
       } 

       @Override 
       public void onFacebookError(FacebookError e, Object state) { 
        Log.d("FacebookError", e.toString()); 
       } 
      }); 

Вход

04-29 23:41:35.523: E/AndroidRuntime(1011): java.lang.NullPointerException 
04-29 23:41:35.523: E/AndroidRuntime(1011): at rageup.android.home.onClick(home.java:177) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at android.view.View.performClick(View.java:2364) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at android.view.View.onTouchEvent(View.java:4179) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at android.widget.TextView.onTouchEvent(TextView.java:6541) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at android.view.View.dispatchTouchEvent(View.java:3709) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:1659) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1107) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at android.app.Activity.dispatchTouchEvent(Activity.java:2061) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1643) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at android.view.ViewRoot.handleMessage(ViewRoot.java:1691) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at android.os.Handler.dispatchMessage(Handler.java:99) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at android.os.Looper.loop(Looper.java:123) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at android.app.ActivityThread.main(ActivityThread.java:4363) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at java.lang.reflect.Method.invokeNative(Native Method) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at java.lang.reflect.Method.invoke(Method.java:521) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) 
04-29 23:41:35.523: E/AndroidRuntime(1011): at dalvik.system.NativeStart.main(Native Method) 
04-29 23:41:35.534: I/dalvikvm(1011): threadid=7: reacting to signal 3 
04-29 23:41:35.534: E/dalvikvm(1011): Unable to open stack trace file '/data/anr/traces.txt': Permission denied 
04-29 23:41:37.283: I/Process(1011): Sending signal. PID: 1011 SIG: 9 

Любые предложения относительно того, почему это может происходить? Исключение Null Pointer относится к первой строке второго блока кода.

Answer 1

ваш mAsyncRunner, кажется null.

Вы инициализировали его?

инициализировать это что-то вроде этого:

mAsyncRunner = new AsyncFacebookRunner(mFacebook); //mFacebook is your facebook object. 

Answer 2

попытка ниже кода,

public void logout(final Context context, 
        final RequestListener listener, 
        final Object state) { 
    new Thread() { 
     @Override public void run() { 
      try { 
       String response = fb.logout(context); 
       if (response.length() == 0 || response.equals("false")){ 
        listener.onFacebookError(new FacebookError(
          "auth.expireSession failed"), state); 
        return; 
       } 
       listener.onComplete(response, state); 
      } catch (FileNotFoundException e) { 
       listener.onFileNotFoundException(e, state); 
      } catch (MalformedURLException e) { 
       listener.onMalformedURLException(e, state); 
      } catch (IOException e) { 
       listener.onIOException(e, state); 
      } 
     } 
    }.start(); 
} 

public void logout(final Context context, final RequestListener listener) { 
    logout(context, listener, /* state */ null); 
} 

Answer 3

проверить, является ли нулевой контекст или нет, и пытаются использовать

facebook.logout(this);