Question

I am currently using only Social.framework (no FacebookSDK) and getting starting with requesting and getting access to basic user data. Here’s all the code I have (with a few properties declared outside, as you’ll notice). Everything works fine in terms of getting the right permissions, but I’m getting the following output error when asking for user’s profile picture:

2013-01-27 21:28:44.324 TestApp[9230:1a703] Account saved to accountStore
2013-01-27 21:28:45.002 TestApp[9230:1d603] (null)
2013-01-27 21:28:45.003 TestApp[9230:1d603] Request error: The operation couldn’t be     completed. (Cocoa error 3840.)

And here is the code:

- (IBAction)btnFbLoginPressed:(id)sender
{
ACAccountType *fbAccountType = [self.accountStore accountTypeWithAccountTypeIdentifier: ACAccountTypeIdentifierFacebook];
NSArray *permissions = @[@"email"];
self.requestAccessOptions = @{ACFacebookAppIdKey:FB_API_KEY, ACFacebookPermissionsKey:permissions, ACFacebookAudienceKey:ACFacebookAudienceOnlyMe};

[self.accountStore requestAccessToAccountsWithType:fbAccountType options:self.requestAccessOptions completion:^(BOOL granted, NSError *e) {
    if (granted && e == nil) {

        NSArray *readPermissions = @[@"user_photos"];
        NSDictionary *readAcccessOptions = @{ACFacebookAppIdKey:FB_API_KEY, ACFacebookPermissionsKey:readPermissions, ACFacebookAudienceKey:ACFacebookAudienceOnlyMe};

        [self.accountStore requestAccessToAccountsWithType:fbAccountType options:readAcccessOptions completion:^(BOOL granted, NSError *e) {
            if (granted && e == nil) {

                NSArray *accounts = [self.accountStore accountsWithAccountType:fbAccountType];
                self.facebookAccount = [accounts lastObject];

                [self.accountStore saveAccount:self.facebookAccount withCompletionHandler:^(BOOL success, NSError *error) {
                    if (error != nil || !success) {
                        NSLog(@"Error saving account to accountStore: %@", error.localizedDescription);
                    } else {
                        NSLog(@"Account saved to accountStore");
                    }
                }];

                NSString *uid = [NSString stringWithFormat:@"%@", [[self.facebookAccount valueForKey:@"properties"] valueForKey:@"uid"]];
                NSString *url = [NSString stringWithFormat:@"https://graph.facebook.com/%@/picture", uid];
                NSURL *profilePictureURL = [NSURL URLWithString:url];

                SLRequest *profilePictureRequest = [SLRequest requestForServiceType:SLServiceTypeFacebook requestMethod:SLRequestMethodGET URL:profilePictureURL parameters:nil];
                profilePictureRequest.account = self.facebookAccount;

                [profilePictureRequest performRequestWithHandler:^(NSData *responseData, NSHTTPURLResponse *urlResponse, NSError *e)
                 {
                     NSDictionary *responseDataDictionary = [NSJSONSerialization JSONObjectWithData:responseData options:NSJSONReadingAllowFragments error:&e];
                     NSLog(@"%@", responseDataDictionary);
                     if (e != nil) {
                         NSLog(@"Request error: %@", e.localizedDescription);
                     } else {

                     }
                 }];

            } else {
                NSLog(@"Read permissions request error: %@", e.localizedDescription);
            }
        }];

    } else {
        NSLog(@"Basic permissions request error: %@", e.localizedDescription);
    }
}];
}

You can see that the reponseDataDictionary is null and something happens when parsing the data. I noticed a couple of other threads on SO about the same error code, but no luck so far. My guess is that either 1) there’s something wrong with my Facebook code, or 2) I’m parsing the data incorrectly. Any help’s appreciated!

Note: I would like to stick to using the Social/Account frameworks only.

UPDATE: Slight modification thanks to a suggestion in the comments.

Changed code:

[profilePictureRequest performRequestWithHandler:^(NSData *responseData, NSHTTPURLResponse *urlResponse, NSError *e)
{
   NSLog(@"Request error value: %@", e.localizedDescription);

   NSError *jsonError = nil;
   NSDictionary *responseDataDictionary = [NSJSONSerialization JSONObjectWithData:responseData options:NSJSONReadingAllowFragments error:&jsonError];
   NSLog(@"Response data dictionary value: %@", responseDataDictionary);
   if (jsonError != nil) {
       NSLog(@"Serialization error: %@", jsonError.localizedDescription);
   } else {
       NSLog(@"Serialization successful");
   }
}];

Output:

2013-01-28 18:55:16.265 TestApp[9565:1ae03] Account saved to accountStore
2013-01-28 18:55:17.640 TestApp[9565:1b503] Request error value: (null)
2013-01-28 18:55:17.640 TestApp[9565:1b503] Response data dictionary value: (null)
2013-01-28 18:55:17.642 TestApp[9565:1b503] Serialization error: The operation couldn’t be completed. (Cocoa error 3840.)

Answer 1

The profilePictureRequest is returning an image and not JSON. Use + (CIImage *)imageWithData:(NSData *)data to convert the response to an image.