Using facebook login correctly

Question

In my application on the start page I ask the user to authenticate via Facebook, then I request for some permissions and fetch some information:

LoginButton authButton = (LoginButton) view.findViewById(R.id.authButton);
        authButton.setFragment(this);
        authButton.setReadPermissions(Arrays.asList("user_likes", "user_status"));
        fb = new FacebookMain(); 

I am able to get all this information, but moving to my next page I want to give a button on my listview and from there a user can post on a friends wall. I followed the HelloFacebook sample and it works like a charm, however in my case when I try to implement it in a fragment it does not work as intended, I dont want the user to login every time he wants to post (I am using an additional permission here -- to post) DO I have to implement all the lifecycly events here, in this fragment? Is there any other or recommended approach to this?

Currently what I am doing is:

my class declaration:

public class FragmentTab1 extends Fragment {

Class level variables:

String FACEBOOK_ID;
String IMAGE_CONTENT;
EditText SEARCH; 
private static final String PERMISSION = "publish_actions";
Session session;
private final String PENDING_ACTION_BUNDLE_KEY = "com.exa.digitalrem:PendingAction";
private PendingAction pendingAction = PendingAction.NONE;
private GraphUser user1;
private UiLifecycleHelper uiHelper;

Functions related to facebook:

private PendingAction pendingAction = PendingAction.NONE;
private GraphUser user1;

private enum PendingAction {
    NONE, POST_PHOTO, POST_STATUS_UPDATE
}



private Session.StatusCallback callback = new Session.StatusCallback() {
    @Override
    public void call(Session session, SessionState state,
            Exception exception) {
        onSessionStateChange(session, state, exception);
    }
}; 

public static boolean isActive() {
    Session session = Session.getActiveSession();
    if (session == null) {
        return false;
    }
    return session.isOpened();
}


private void onSessionStateChange(Session session, SessionState state,
            Exception exception) {
        if (pendingAction != PendingAction.NONE && (exception instanceof FacebookOperationCanceledException || exception instanceof FacebookAuthorizationException)) {
            new AlertDialog.Builder(getActivity()) .setTitle("cancelled").setMessage("NotGranted").setPositiveButton("Ok", null).show();
            pendingAction = PendingAction.NONE;
        } else if (state == SessionState.OPENED_TOKEN_UPDATED) {
            handlePendingAction();
        }
        updateUI();
    }

    private void updateUI() {
        Session session = Session.getActiveSession();
        boolean enableButtons = (session != null && session.isOpened());



        if (enableButtons && user1 != null) {
            //  profilePictureView.setProfileId(user.getId());
            //  greeting.setText(getString(R.string.app_name, user.getFirstName()));
        } else {
            //  profilePictureView.setProfileId(null);
            //  greeting.setText(null);
        }
    }

    @SuppressWarnings("incomplete-switch")
    private void handlePendingAction() {
        PendingAction previouslyPendingAction = pendingAction;
        // These actions may re-set pendingAction if they are still pending, but
        // we assume they
        // will succeed.
        pendingAction = PendingAction.NONE;

    } 

In the onCreate:

 uiHelper = new UiLifecycleHelper(getActivity(), callback);
 uiHelper.onCreate(savedInstanceState);


    if (savedInstanceState != null) {
            name = savedInstanceState.getString(PENDING_ACTION_BUNDLE_KEY);
            pendingAction = PendingAction.valueOf(name);
        }

        //===============================================

        Session.openActiveSessionFromCache(getActivity());

        //================================================

This is my facebook post method, I call this on a button click, which is in a listview:

public void postFB(String id) {
        System.out.println("in fb");
        if (isNetworkConnected()) {
            Session session = Session.getActiveSession();
            if (session != null) {
                System.out.println("session not null");
                if (hasPublishPermission()) {
                    //do something

                    WebDialog feedDialog = (new WebDialog.FeedDialogBuilder(
                            getActivity(), Session.openActiveSessionFromCache(getActivity()),
                            params)).setOnCompleteListener(
                                    new OnCompleteListener() {

                                        @Override
                                        public void onComplete(Bundle values,
                                                FacebookException error) {
                                            // frag3.setFbId(null);
                                            // ---------------------------- got to put
                                            // check here
                                            //  onBackPressed();

                                        }
                                    }).build();
                    feedDialog.show();
                } else if (session.isOpened()) {
                    // We need to get new permissions, then complete the action
                    // when we get called back.

                    session.requestNewPublishPermissions(new Session.NewPermissionsRequest(
                            getActivity(), PERMISSION));
                    // do something

                    WebDialog feedDialog = (new WebDialog.FeedDialogBuilder(
                            getActivity(), Session.getActiveSession(),
                            params)).setOnCompleteListener(
                                    new OnCompleteListener() {

                                        @Override
                                        public void onComplete(Bundle values,
                                                FacebookException error) {
                                            // frag3.setFbId(null);
                                            // ---------------------------- got to put
                                            // check here
                                            //onBackPressed();

                                        }
                                    }).build();
                    feedDialog.show();
                }
            }else if(session == null){
                System.out.println("login");
            }
        } else {
            Toast.makeText(getActivity(),
                    "Please check your internet connection", Toast.LENGTH_LONG)
                    .show();
        }
    }

This however does not seem to me a correct approach, is there any better way? Also how do I detect if the user session is expired and prompt the user to login again? The Docs dont seem to reveal the internal functioning of the Login button?

Answer 1

Do not start a new session .... change it in the source code

private Session.StatusCallback callback = new Session.StatusCallback() {
@Override
public void call(Session session, SessionState state,
        Exception exception) {
    onSessionStateChange(session, state, exception);
}
};

Answer 2

• Add the facebook SDK in your project

• Add below lines in AndroidManifest.xml under tag

      <activity android:name="com.facebook.LoginActivity" />
  

• Also Add facebook app id in string.xml

• Declare the private members

  private boolean isOnCreate;
  private List<String> permissions = new ArrayList<String>();
  private JSONObject facebookObject;
  private ProgressDialog progressDialog;
  
  /** The callback. */
  private final com.facebook.Session.StatusCallback callback = new 
  
  com.facebook.Session.StatusCallback() {
  @Override
  public void call(Session session, SessionState state, Exception exception) {
  SignInActivity.this.onSessionStateChange(session, state, exception);
  }
  };
  
  private void onSessionStateChange(Session session, SessionState state, Exception         exception) {
  
  if (state == SessionState.OPENED) {
  if (this.isOnCreate) {
   this.isOnCreate = false;
   return;
       }
       onFacebookLoginDone();
  } else if (state == SessionState.CLOSED_LOGIN_FAILED) {
  showErrorMessage();
  }
  }
  
  
      @Override
      public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      Session session = Session.getActiveSession();
      if (session == null) {
          session = new Session(this);
          session.closeAndClearTokenInformation();
      }
      Session.setActiveSession(session);
      }
  
      @Override
      public void onClick(View v) {
      switch (v.getId()) {
  
      case R.id.btn_fb_login:
          this.loginUsingFacebook();
          break;
  
      default:
          break;
      }
  
      }
  
  
      @Override
      protected void onActivityResult(int requestCode, int resultCode, Intent data) {
  
      super.onActivityResult(requestCode, resultCode, data);
      Session.getActiveSession().onActivityResult(this, requestCode, resultCode, data);
      }
  
      /**
       * Login using facebook.
       */
      private void loginUsingFacebook() {
      isOnCreate = false;
      final Session session = Session.getActiveSession();
      if (session != null && session.getState().equals(SessionState.OPENED)) {
          Session.openActiveSession(this, true, this.callback);
          onFacebookLoginDone();
      } else {
          final Session.OpenRequest temp = new Session.OpenRequest(this);
          this.permissions.clear();
          this.permissions.add(UserClass.EMAIL);
          this.permissions.add("user_location");
          temp.setPermissions(this.permissions);
          temp.setCallback(this.callback);
          session.openForRead(temp);
      }
  
      }
  
      /**
       * On facebook login done.
       */
      private void onFacebookLoginDone() {
  
      final Bundle bundle = new Bundle();
      bundle.putString("fields", "first_name,last_name,id,location,locale,username,email,verified");
      new PerformSignUpOnServer("/me", bundle).execute();
      }
  
      /**
       * The Class PerformSignUpOnServer.
       */
      private class PerformSignUpOnServer extends AsyncTask<Void, Void, Void> {
  
      /** The server url. */
      private String serverURL;
  
      /** The server bundle. */
      private Bundle serverBundle;
  
      /**
       * Instantiates a new perform sign up on server.
       * 
       * @param url
       *            the url
       * @param bundle
       *            the bundle
       */
      public PerformSignUpOnServer(String url, Bundle bundle) {
  
          this.serverBundle = bundle;
          this.serverURL = url;
      }
  
      /*
       * (non-Javadoc)
       * 
       * @see android.os.AsyncTask#onPreExecute()
       */
      @Override
      protected void onPreExecute() {
          progressDialog = ProgressDialog.show(SignInActivity.this, "", "Loading...");
          super.onPreExecute();
      }
  
      /*
       * (non-Javadoc)
       * 
       * @see android.os.AsyncTask#doInBackground(Params[])
       */
      @Override
      protected Void doInBackground(Void... params) {
  
          signUpUserOnServer(this.serverURL, this.serverBundle);
  
          return null;
  
      }
  
      /*
       * (non-Javadoc)
       * 
       * @see android.os.AsyncTask#onPostExecute(java.lang.Object)
       */
      @Override
      protected void onPostExecute(Void result) {
  
  
      }
      }
  
      /**
       * Sign up user on server.
       * 
       * @param url
       *            the url
       * @param bundle
       *            the bundle
       */
      private void signUpUserOnServer(String url, Bundle bundle) {
      final Session session = Session.getActiveSession();
      if (session != null && session.isClosed() == false) {
          final Request userInformation = new Request(session, url, bundle, HttpMethod.GET);
          final Response response = userInformation.executeAndWait();
          facebookObject = response.getGraphObject().getInnerJSONObject();
          Log.d("json", facebookObject.toString());
      }
      }
  
      /**
       * On session state change.
       * 
       * @param state
       *            the state
       */
      private void onSessionStateChange(SessionState state) {
  
      if (state == SessionState.OPENED) {
          if (isOnCreate) {
          isOnCreate = false;
          return;
          }
          onFacebookLoginDone();
      }
      }
  

  See your log cat with tag "json" you will have a facebook object