iOS Facebook SDK 3.1 openActiveSessionWithReadPermissions：检测用户何时未授予访问权限

我需要知道在openActiveSessionWithReadPermissions执行期间，用户何时未授予Facebook对我的应用程序的访问权限。（未授予，意味着开关在设置->Facebook->我的应用程序下设置为“关闭”。）

以下是未授予权限时的错误：

Error Domain=com.facebook.sdk Code=2“操作无法完成。（com.facebook.sdk错误2.）”UserInfo=0x1fd46780{com.facebook.sdk:ErrorLoginFailedReason=com.facebook.sdk:ErrorLoginFailedReason}

为了进行比较，以下是无网络的错误：

Error Domain=com.facebook.sdk Code=2“该操作无法完成。（com.facebook.sdk错误2.）“UserInfo=0x1edf2eb0{com.facebook.sdk:ErrorLoginFailedReason=com.facebook.sdk:ErrorLoginFailedReason，com.facebook.sdk:ErrorInnerErrorKey=ErrorDomain=NSURlerErrorDomain代码=-1009”Internet连接似乎处于脱机状态UserInfo=0x1ed47a20{NSErrorFailingURLKey=https://api.facebook.com/method/auth.iosauthorizeapp，NSErrorFailingURLStringKey=https://api.facebook.com/method/auth.iosauthorizeapp，NSLocalizedDescription=Internet连接似乎处于脱机状态。}

是否有一种简单的方法来检测用户何时未被授权？我是否只在UserInfo字典中查找错误代码2和一个键/值对

---

我希望Facebook能像accountstorerequestaccesscompletionhandler一样给我们一个

BOOL，我没有找到一个好的解决方案。我用这个：

[FBSession openActiveSessionWithReadPermissions:FACEBOOK_READ allowLoginUI:YES 
    completionHandler:^(FBSession *session, FBSessionState state, NSError *error) {

    // find error for not granted
    if(error && error.code == 2) {
        NSDictionary *userInfo = error.userInfo;
        if(userInfo && userInfo.count == 1) {
            [self fallbackLogin];
            return;
        }
    }
    [self sessionStateChanged:session state:state error:error];
}];

- (void)fallbackLogin {

    // use deprecated
    [FBSession openActiveSessionWithPermissions:FACEBOOK_READ allowLoginUI:YES
completionHandler:^(FBSession *session, FBSessionState state, NSError *error) {
          [self sessionStateChanged:session state:state error:error];
    }];   
}

您可以使用以下代码检查权限：

- (void)checkForPermissions {
    // We will request the user's public profile and the user's birthday
    // These are the permissions we need:
    NSArray *permissionsNeeded = @[@"basic_info", @"email"];
    // Request the permissions the user currently has
    [FBRequestConnection startWithGraphPath:@"/me/permissions"
                          completionHandler:^(FBRequestConnection *connection, id result, NSError *error) {
                          //If there is error, handle it accordingly.

                          //Results contains all the permissions user has granted the app.
                          //If you do not have the desired permissions, reauthorize the app
                          // Ask for the missing permissions
                          //requestPermissions = array of permissions to be asked
                          [FBSession.activeSession
                           requestNewReadPermissions:requestPermissions
                           completionHandler:^(FBSession *session, NSError *error) {
                               //Handle the session object as per your requirements.
                           }];
                      }];
}

希望这有帮助。
您找到解决方案了吗？