iOS: Connect to Facebook without leaving the app for authorization

Question

I know that it was possible before the Graph API.

I work on an iPhone app that may not be in the background (one of the requirements).
In addition there is a log

Answer 1

In Facebook.m

- (void)authorizeWithFBAppAuth:(BOOL)tryFBAppAuth
                    safariAuth:(BOOL)trySafariAuth {
  NSMutableDictionary* params = [NSMutableDictionary dictionaryWithObjectsAndKeys:
                                 _appId, @"client_id",
                                 @"user_agent", @"type",
                                 kRedirectURL, @"redirect_uri",
                                 @"touch", @"display",
                                 kSDKVersion, @"sdk",
                                 nil];

method comment out this

 UIDevice *device = [UIDevice currentDevice];
  if ([device respondsToSelector:@selector(isMultitaskingSupported)] && [device isMultitaskingSupported]) {
    if (tryFBAppAuth) {
      NSString *fbAppUrl = [FBRequest serializeURL:kFBAppAuthURL params:params];
      didOpenOtherApp = [[UIApplication sharedApplication] openURL:[NSURL URLWithString:fbAppUrl]];
    }

    if (trySafariAuth && !didOpenOtherApp) {
      NSString *nextUrl = [NSString stringWithFormat:@"fb%@://authorize", _appId];
      [params setValue:nextUrl forKey:@"redirect_uri"];

      NSString *fbAppUrl = [FBRequest serializeURL:loginDialogURL params:params];
      didOpenOtherApp = [[UIApplication sharedApplication] openURL:[NSURL URLWithString:fbAppUrl]];
    }
  }

This will prevent the app from going to background and show you the standard fb dialog.

Answer 2

Here you have an alternative solution.

If you don't like to change the facebook sdk code and want a solution that allows you to choose between SSO or the old-fashioned mechanism, you can Implement an extension like this:

//Facebook_SSOExtension.h
--------------------------------------------------------

@interface Facebook(SSOExtension)
-(void) authorize:(NSArray*)permissions useSSO:(BOOL) useSSO;
@end

//Facebook_SSOExtension.m
--------------------------------------------------------

//So warnings do not appear
@interface Facebook(PrivateSSOExtension)
- (void)authorizeWithFBAppAuth:(BOOL)tryFBAppAuth
                    safariAuth:(BOOL)trySafariAuth;
-(void) setPermissions:(NSArray*) permissions;
@end 

@implementation Facebook(SSOExtension)
-(void) authorize:(NSArray*)permissions useSSO:(BOOL) useSSO
{
    [self setPermissions: permissions];
    [self authorizeWithFBAppAuth:useSSO safariAuth:useSSO];
}
@end

Even though this requires more work than commenting-out the sso code, you will be able to update the facebook-sdk without major problems (if they rename authorizeWithFBAppAuth:safariAuth: your extension will not work, use asserts to detect this issue quickly). Also, if you are building a reusable component to interact with facebook without repeating things over and over again, this will save you some work too.

Cheers.