Android Facebook 处理会话

Question

我正在尝试使用 facebook sdk for android 获取我的 facebook 帐户的用户名和用户 ID，我正在使用以下 sn-p 代码：

final Session session = Session.getActiveSession();
    if (session != null && session.isOpened()) {
        // If the session is open, make an API call to get user data
        // and define a new callback to handle the response
        Request request = Request.newMeRequest(session, new Request.GraphUserCallback() {
            @Override
            public void onCompleted(GraphUser user, Response response) {
                // If the response is successful
                if (session == Session.getActiveSession()) {
                    if (user != null) {
                        user_ID = user.getId();//user id
                        profileName = user.getName();//user's profile name
                        userNameView.setText(user.getName());
                    }   
                }   
            }   
        }); 
        Request.executeBatchAsync(request);
    } 

问题是会话为空，我应该如何处理会话管理？我的意思是激活会话的代码和停用会话的代码？ 我想使用自己的退出和登录按钮自己处理与 facebook 的会话，但找不到管理会话的代码。

提前非常感谢！

Answer 1

您的Session.getActiveSession() 是null，因为您没有正确初始化会话。 看看下面的代码：

public class MyActivity extends Activity {

private UiLifecycleHelper uiHelper;
    private Session.StatusCallback callback = new Session.StatusCallback() {
        @Override
        public void call(final Session session, final SessionState state, final Exception exception) {
        /** If your session status has changed you can dead with that using this callback. */
       }
    };

@Override
    protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
       // Your code goes here

       /* Initializing a valid session. */
       uiHelper = new UiLifecycleHelper(this, callback); //callback can be null
       uiHelper.onCreate(savedInstanceState);

       Settings.addLoggingBehavior(LoggingBehavior.INCLUDE_ACCESS_TOKENS);
    }

@Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
      super.onActivityResult(requestCode, resultCode, data);
      uiHelper.onActivityResult(requestCode, resultCode, data);}
    }

@Override
    protected void onPause() {
     super.onPause();
     uiHelper.onPause();
    }

@Override
    protected void onStop() {
     super.onStop();
     Session.getActiveSession().removeCallback(callback);
    }

    @Override
    public void onDestroy() {
    super.onDestroy();
     uiHelper.onDestroy();
    }
}

如果这对你有用，请告诉我。