FBSDK (New Facebook SDK 4.0) Implementation is not working for Login with Facebook

Question or problem in the Swift programming language:

I am using this following block which is mentioned in Facebook Developer. But when my App callbacks from Browser then it is always returning Cancelled result.

FBSDKLoginManager *login = [[FBSDKLoginManager alloc] init];
[login logInWithReadPermissions:@[@"email"]     
        handler:^(FBSDKLoginManagerLoginResult *result, NSError *error) {
  if (error) {
        // Process error
   }
  else if (result.isCancelled) {
        // Handle cancellations
   }
   else {
       // If you ask for multiple permissions at once, you
       // should check if specific permissions missing
       if ([result.grantedPermissions containsObject:@"email"]) {
        // Do work
       }
  }
 }];

If anyone used this then please share it with me.

Reference : https://developers.facebook.com/docs/ios/getting-started

How to solve the problem:

Solution 1:

You must add the following method in your appDelegate

- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation {
    return [[FBSDKApplicationDelegate sharedInstance] application:application
                                                          openURL:url
                                                sourceApplication:sourceApplication
                                                       annotation:annotation];
}

If the above method is not present into AppDelegate then it results into cancelled state.

Refer to : https://developers.facebook.com/docs/ios/getting-started#startcoding

Solution 2:

You use this simple block with your expected requirements

if ([FBSDKAccessToken currentAccessToken])
{
      [[[FBSDKGraphRequest alloc] initWithGraphPath:@"me" parameters:nil]
                 startWithCompletionHandler:^(FBSDKGraphRequestConnection *connection, id user, NSError *error)
       {
           if (!error)
           {
            //  NSDictionary *dictUser = (NSDictionary *)user;
            // This dictionary contain user Information which is possible to get from Facebook account.
           }
        }];
}

Access Token you will get only and only after successfully login

Hope this will help you

Solution 3:

To get user profile try this

if ([FBSDKAccessToken currentAccessToken])
                {
                    [[[FBSDKGraphRequest alloc] initWithGraphPath:@"me" parameters:nil]
                     startWithCompletionHandler:^(FBSDKGraphRequestConnection *connection, id user, NSError *error)
                     {
                         if (!error) {
                             NSDictionary *dictUser = (NSDictionary *)user;
                             self.txfName.text      = [dictUser objectForKeyNotNull:@"name"];
                             self.txfEmail.text     = [dictUser objectForKeyNotNull:@"email"];
                             self.txfUserName.text  = [[dictUser objectForKey:@"first_name"] lowercaseString];
                             NSLog(@"image : https://graph.facebook.com/%@/picture?type=small",[dictUser objectForKeyNotNull:@"id"]);
                         }
                     }];
                }

Hope this would help you

Solution 4:

You cant get Email id from Facebook Login….why???

If your Facebook account registered using “Mobile Number”, and you do not have Email in same account.

Check this scenario. This might be happening, We cant blame for it to FBSDK.

Hope this will clear some points.

Solution 5:

For me, the following line caused isCancelled to always be true… idk why

[login logInWithReadPermissions:@[@"public_profile", @"email", @"gender"] 

After changing to this… it worked

[login logInWithReadPermissions:@[@"public_profile"] 

Hope this helps!