Question

Here is my code:

    mPrefs = getSharedPreferences("facebook_session",MODE_PRIVATE);
    String access_token = mPrefs.getString("access_token", null);
    long expires = mPrefs.getLong("access_expires", 0);

    if(access_token != null) {
        facebook.setAccessToken(access_token);
        Log.i("access_token","facebook.setAccessToken(access_token), and access_token=="+access_token);

    }
    if(expires != 0) {
        Log.i("expires","facebook.setAccessToken(access_token), and expires=="+expires);
        facebook.setAccessExpires(expires);
    }


    /*
     * Only call authorize if the access_token has expired.
     */

    if(!facebook.isSessionValid()) {
    Log.v("in !facebook.isSessionValid()", "no pref");

    facebook.authorize( this, new String[] { "email", "publish_checkins" }, new DialogListener(){
        @Override
        public void onComplete(Bundle values) {
            Log.v("facebook.authorize", "no pref");
            Log.v("postToWall","mFacebook.getAccessToken(): "+facebook.getAccessToken());
            Log.v("postToWall","mFacebook.getAccessExpires(): "+facebook.getAccessExpires());

            SharedPreferences.Editor editor = mPrefs.edit();
            editor.putString("access_token", facebook.getAccessToken());
            editor.putLong("access_expires", facebook.getAccessExpires());
            editor.commit();

        }
        @Override
        public void onFacebookError(FacebookError e) {
            Log.v("facebook.authorize","mFacebook.onFacebookError(): "+e);
        }
        @Override
        public void onError(DialogError e) {
            Log.v("facebook.authorize","mFacebook.onFacebookError(): "+e);
            Log.v("facebook.authorize","mFacebook.onError(): "+facebook.getAccessToken());
        }
        @Override
        public void onCancel() {
            Toast.makeText(getApplicationContext(),
                    "You must be registered and signed in to perform that action",
                    Toast.LENGTH_LONG).show();
            finish();
            // onCancel, leaving the app
        }
    });   
    }//end of pref check

and in the logout function, I tried to logout form facebook and clear the sharedPreferences as well:
public void Logout(View view){

      String access_token = mPrefs.getString("access_token", null);
      Log.i("access_token","mPrefs.getString(access_token, null), and access_token=="+access_token);

      SharedPreferences.Editor editor = mPrefs.edit();
      editor.remove("access_token");
      editor.remove("access_expires");
      editor.commit();
      Log.i("access_token","mPrefs.getString(access_token, null), and access_token=="+access_token);

      mAsyncRunner = new AsyncFacebookRunner(facebook); // initialize AsyncRunner, make sure it's not null
      mAsyncRunner.logout(Login.this, new RequestListener() {
          @Override
          public void onComplete(String response, Object state) {
              finish();
          }

          @Override
          public void onIOException(IOException e, Object state) {}

          @Override
          public void onFileNotFoundException(FileNotFoundException e,
                Object state) {}

          @Override
          public void onMalformedURLException(MalformedURLException e,
                Object state) {}

          @Override
          public void onFacebookError(FacebookError e, Object state) {}
        });
  }

So, here is the question: No matter how hard I try, the values stored in sharedPreferences didn’t change. I tried clear(), remove(), commit(), apply() etc…..
Please help!

Answer 1

  Log.i("access_token","mPrefs.getString(access_token, null), and access_token=="+access_token);

If you are using this Log statement to verify whether the values stored in SharedPreferences are cleared or not, you are not doing it correctly.

Your value access_token was assigned a value before you removed it, so when you reference the variable it will still retain that value. To correctly test whether the value has been removed from SharedPreferences, you need to try accessing that value again after you’ve removed it by doing the following after your editor.commit() command:

String access_token_2 = mPrefs.getString("access_token", null);
Log.i("access_token", "access_token from SharedPreferences is now " + access_token_2);