Facebook Login - If user account is present (and app is not installed) login fails

Question

I have just found this issue whilst testing my application and it is really starting to annoy me. So what the environment is like is as follows :

• No Facebook App installed
• User is logged into iOS System Account (Under settings -> Facebook)

When my app attempts to authenticate the user for the first time it provides this wall of text : ( I tried cleaning it up a little)

2014-01-30 15:20:31.439 Unifeed[2140:70b] Session is <FBSession: 0xb74f9e0, state:         
FBSessionStateClosedLoginFailed, 
loginHandler: 0x0, appID: *************, urlSchemeSuffix: ,    
 tokenCachingStrategy:<FBSessionTokenCachingStrategy: 0xb73bd90>,
 expirationDate: (null),     
refreshDate: (null), attemptedRefreshDate: 0001-12-30 00:00:00 +0000, permissions:(null)>

2014-01-30 15:20:31.440 Unifeed[2140:70b] Session closed
2014-01-30 15:20:31.440 Unifeed[2140:70b] User logged out

2014-01-30 15:20:31.441 Unifeed[2140:70b] Error occured Error Domain=com.facebook.sdk Code=2    
"The operation couldn’t be completed. (com.facebook.sdk error 2.)"
UserInfo=********  
{com.facebook.sdk:ErrorLoginFailedReason=com.facebook.sdk:SystemLoginCancelled,    
com.facebook.sdk:ErrorInnerErrorKey=Error Domain=com.apple.accounts Code=7 "The operation 
couldn’t be completed. (com.apple.accounts error 7.)", 
com.facebook.sdk:ErrorSessionKey=<FBSession: 0xb74f9e0, state: FBSessionStateClosedLoginFailed,   
loginHandler: 0x0, appID: ************, urlSchemeSuffix: 
, tokenCachingStrategy:<FBSessionTokenCachingStrategy: 
0xb73bd90>, expirationDate: (null), refreshDate: (null), 
attemptedRefreshDate: 0001-12-30 00:00:00 +0000, permissions:(null)>}

2014-01-30 15:20:31.441 Unifeed[2140:70b] User cancelled login
2014-01-30 15:20:31.445 Unifeed[2140:70b] User logged out

I know thats slightly confusing but my take on it is its erring out because it thinks the user cancelled the login process. The thing is I never see the little pop up asking me if I want to login or to accept the permissions.... So I added the Facebook app to the phone and it worked... well thats great but what if I have a user with not App but they have FB logged in on the phone.... Anyone have any ideas?

My code for authentication is as follows : (Pretty much just a little modified from FB website)

- (void) facebookSessionChange {
// If the session state is any of the two "open" states when the button is clicked
if (FBSession.activeSession.state == FBSessionStateOpen
    || FBSession.activeSession.state == FBSessionStateOpenTokenExtended) {

    // Close the session and remove the access token from the cache
    // The session state handler (in the app delegate) will be called automatically
    [FBSession.activeSession closeAndClearTokenInformation];

    // If the session state is not any of the two "open" states when the button is clicked
} else {
    // Open a session showing the user the login UI
    [FBSession openActiveSessionWithReadPermissions:permissions
                                       allowLoginUI:YES
                                  completionHandler:
     ^(FBSession *session, FBSessionState state, NSError *error) {
         [self sessionStateChanged:session state:state error:error];
     }];
}
 }

 - (void)sessionStateChanged:(FBSession *)session state:(FBSessionState) state error:(NSError *)error
 {

NSLog(@"Session is %@", session);
// If the session was opened successfully
if (!error && state == FBSessionStateOpen){
    NSLog(@"Session opened");
    // Show the user the logged-in UI
    [self userLoggedIn];
    return;
}
if (state == FBSessionStateClosed || state == FBSessionStateClosedLoginFailed){
    // If the session is closed
    NSLog(@"Session closed");
    // Show the user the logged-out UI
    [self userLoggedOut];
}

// Handle errors
if (error){
    NSLog(@"Error occured %@", error);
    if ([FBErrorUtility shouldNotifyUserForError:error] == YES){
        NSLog(@"Error occured %@", error);
    } else {

        // If the user cancelled login, do nothing
        if ([FBErrorUtility errorCategoryForError:error] == FBErrorCategoryUserCancelled) {
            NSLog(@"User cancelled login");

            // Handle session closures that happen outside of the app
        } else if ([FBErrorUtility errorCategoryForError:error] == FBErrorCategoryAuthenticationReopenSession){
            NSLog(@"Session is no longer valid");

        } else {
            //Get more error information from the error
            NSDictionary *errorInformation = [[[error.userInfo objectForKey:@"com.facebook.sdk:ParsedJSONResponseKey"] objectForKey:@"body"] objectForKey:@"error"];
            NSLog(@"Error occured : %@", [errorInformation objectForKey:@"message"]);
        }
    }
    // Clear this token
    [FBSession.activeSession closeAndClearTokenInformation];
    // Show the user the logged-out UI
    [self userLoggedOut];
}
}

// Show the user the logged-out UI
- (void)userLoggedOut 
{
    NSLog(@"User logged out");
}

// Show the user the logged-in UI
- (void)userLoggedIn 
{
    NSLog(@"User Logged in");
    [_delegate doneLogginginToFb];
}

I have tried changing the way I authenticate but always run into the same problem... Any ideas?

Thanks

A

Answer 1

I think I did reproduce your error here, your application was denied access to Facebook account in settings (for some reason, maybe you clicked on "don't allow" ...) after the user deny the access or turn off the switch in Facebook settings, the application will not ask again for the permission and every time you will try to connect it will fail with a FBErrorCategoryUserCancelled state.

To fix this go to Settings > General > Reset, and then reset the Location & Privacy. After that run your application, you should be able to see the prompt asking for permissions.