iOS Facebook SDK 3.1 openActiveSessionWithReadPermissions : Detect when user is not granting access

Question

我需要知道用户在 openActiveSessionWithReadPermissions 执行期间何时未授予 Facebook 访问我的应用程序的权限。 (未授予意味着在“设置”->“Facebook”->“我的应用”下将开关设置为“关闭”。)

这是未授权时的错误:

Error Domain=com.facebook.sdk Code=2 "The operation couldn’t be completed. (com.facebook.sdk error 2.)" UserInfo=0x1fd46780 {com.facebook.sdk:ErrorLoginFailedReason=com.facebook.sdk:ErrorLoginFailedReason}

为了比较，这里是没有网络的错误:

Error Domain=com.facebook.sdk Code=2 "The operation couldn’t be completed. (com.facebook.sdk error 2.)" UserInfo=0x1edf2eb0 {com.facebook.sdk:ErrorLoginFailedReason=com.facebook.sdk:ErrorLoginFailedReason, com.facebook.sdk:ErrorInnerErrorKey=Error Domain=NSURLErrorDomain Code=-1009 "The Internet connection appears to be offline." UserInfo=0x1ed47a20 {NSErrorFailingURLKey=https://api.facebook.com/method/auth.iosauthorizeapp, NSErrorFailingURLStringKey=https://api.facebook.com/method/auth.iosauthorizeapp, NSLocalizedDescription=The Internet connection appears to be offline.}}

是否有一种万无一失的方法来检测用户何时未被授予权限？我是否只在 UserInfo 字典中查找错误代码 2 和一对键/值？

我希望 Facebook 给我们一个 BOOL granted 就像在 ACAccountStoreRequestAccessCompletionHandler 中一样。

Answer 1

@peter-warbo:我没有找到好的解决方案。我正在使用这个:

[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];
    }];   
}