Integrate facebook login and fetch user details along with tabbarcontroller in ios6 - iphone

Question

I have implemented facebook login in my app.
1----> I was able to do facebook login but after that logged in user is able to continue with my app i.e a tabbarController with three tab items appears and simultaneously I need to fetch facebook user details (email,firstname,lastname etc)
But I was unable to retrieve details. I do not understand where am I going wrong.
In my ViewController.m:
- (IBAction)performLogin:(id)sender
{
AppAppDelegate *appDelegate = (AppAppDelegate *) [[UIApplication sharedApplication] delegate];
[appDelegate openSessionWithAllowLoginUI:YES];
UITabBarController *tabBarController=[[UITabBarController alloc]init];
SearchViewController *searchViewController=[[SearchViewController alloc]initWithNibName:#"SearchViewController" bundle:nil];
UProfile *uprofile=[[UProfile alloc]initWithNibName:#"UProfile" bundle:nil];
userprofile.title=#"My Profile";
LogOut *logout=[[LogOut alloc]initWithNibName:#"LogOut" bundle:nil];
logout.title=#"Sign out";
tabBarController.viewControllers=[NSArray arrayWithObjects:searchViewController,uprofile,logout, nil];
[self presentModalViewController:tabBarController animated:YES];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(sessionStateChanged:)
name:FBSessionStateChangedNotification
object:nil];
}
- (void)sessionStateChanged:(NSNotification*)notification {
if (FBSession.activeSession.isOpen) {
[FBRequestConnection
startForMeWithCompletionHandler:^(FBRequestConnection *connection,
id<FBGraphUser> user,
NSError *error) {
if (!error) {
NSString *fbUserEmail= #"";
NSLog(#"%#",user);
fbUserEmail=[user objectForKey:#"email"];
AppAppDelegate *appDelegate = (AppAppDelegate *) [[UIApplication sharedApplication] delegate];
appDelegate.fbEmail=fbUserEmail;
}
}
];
}
}
But here without showing facebook login page I am getting tabbarController and I am unable to retrieve user details.
How can I show facebook login page first and then tabbarController with user details?
After successful login into facebook how can I continue with my app with a tabbarcontroller with first tabitem(corresponding view )selected?
Please help me out in sorting this issue...Please

Answer 1

You will need to set the readPermissions for getting the email for this method, by passing it an NSArray with object "email". The remaining information such as name etc is returned by default.
+ (BOOL)openActiveSessionWithReadPermissions:(NSArray*)readPermissions
allowLoginUI:(BOOL)allowLoginUI
completionHandler:(FBSessionStateHandler)handler;
of the facebook sdk. If im not mistaken, unless specified permission is "email" then the email object of the user dictionary is nil. Modify your state changed handler perhaps to request the user details such as email. Inside the sessionStateChanged: handler if session is open u may call a method that simply does this
if (FBSession.activeSession.isOpen) {
[[FBRequest requestForMe] startWithCompletionHandler:
^(FBRequestConnection *connection,
NSDictionary<FBGraphUser> *user,
NSError *error) {
if (!error) {
NSLog(#"%#", user);
NSLog(#"%#", [user objectForKey:#"email"]);
}
}];
}