ios Facebook integration error when logged out and logged in - ios

Question

I am trying to use Facebook integration into my app. I use the following code to log in.
After i am logged in and when i log out the app relaunches completely from the beginning and also each time the permission is asked. I only want it to ask permission in the first time when i login with a particular user. But it asks always when i log out and try to login back with the Facebook button.
- (IBAction)facebook:(id)sender
{
FBLoginView *loginView=[[FBLoginView alloc]init];
loginView.delegate=self;
loginView.readPermissions = #[#"first_name",
#"last_name",
#"location",
#"id",
#"access_token",
#"email"];
NSArray* permissions = [NSArray arrayWithObjects: #"email", nil];
loginView.readPermissions = #[#"email"];
loginView.readPermissions=permissions;
[FBSession openActiveSessionWithAllowLoginUI:YES];
[FBRequestConnection
startForMeWithCompletionHandler:^(FBRequestConnection *connection,
id<FBGraphUser> user1,
NSError *error)
{
if (!error)
{
firstname=user1.first_name;
lastname=user1.last_name;
city=[user1.location objectForKey:#"name"];
email=user1[#"email"];
fbid=user1.id;
Loggedin=#"Y";
[[NSUserDefaults standardUserDefaults]setObject:Loggedin forKey:#"token"];
[[NSUserDefaults standardUserDefaults]synchronize];
}
NSURL *url = [[NSURL alloc]initWithString:[NSString stringWithFormat:#"%#action=currfbuser&email=%#&fb_id=%#",MainURL,email,fbid ]];
NSError *errors;
NSData *data = [NSData dataWithContentsOfURL:url];
NSDictionary *json = (NSDictionary *)[NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:&errors];
status = json[#"status"];
user = json[#"user"];
if ([status isEqualToString:#"success"])
{
[self performSegueWithIdentifier: #"LogIN" sender: self];
}
else if (!([fbid isEqualToString:#""]))
{
[self performSegueWithIdentifier: #"Facebooksegue" sender: self];
}
NSLog(#"%#",firstname);
NSLog(#"%#",lastname);
NSLog(#"%#",city);
NSLog(#"%#",email);
NSLog(#"%#",fbid);
}];
}
The following code i have used to log out.
- (IBAction)Logout:(id)sender
{
_DetailsView.hidden=YES;
_fade.hidden=YES;
y=0;
Loggedin=#"N";
user=nil;
NSHTTPCookieStorage* cookies = [NSHTTPCookieStorage sharedHTTPCookieStorage];
NSArray* facebookCookies = [cookies cookiesForURL:[NSURL URLWithString:#"http://login.facebook.com"]];
for (NSHTTPCookie* cookie in facebookCookies) {
[cookies deleteCookie:cookie];
}
[FBSession.activeSession closeAndClearTokenInformation];
[[NSUserDefaults standardUserDefaults]setObject:Loggedin forKey:#"token"];
[[NSUserDefaults standardUserDefaults]setObject:user forKey:#"user"];
[[NSUserDefaults standardUserDefaults]synchronize];
[self.navigationController popToRootViewControllerAnimated:YES];
}
This is the first time i am integrating Facebook. So i am not much kind of sure about the code i am using.
The user data fetching is working perfectly fine. The problem is that the app asks for permission each time and if i press Ok or skip for permission both does the same thing that is the app relaunches when i click ok or skip.
The output i obtained has been uploaded in youtube. Please check the following link.
http://youtu.be/ki7BXr8dXmw
I been stuck with this and can't move forward coz of this bug.
Please help me with this and i can give out 50 bounty for the solution when the bounty is available.
Thank you.

Answer 1

Well i have few suggestions. Here you are always opening FB session with login UI.
[FBSession openActiveSessionWithAllowLoginUI:YES];
That is not required always. Once you authorized the user and you got the required permission you no longer needed the login UI. So how will you decide my user is authorized or not?? Just try to login on behalf of user without Login UI (fallback login)
[FBSession openActiveSessionWithAllowLoginUI:NO]; // Should go in viewDidLoad or applicationDidFinishLaunching
If this login attempt success(Taking the cached token), well you have an active FBSession. Now the actual facebook api usage comes. Do a simple check
if (FBSession.activeSession.isOpen)
{
[self getFacebookFriends];
}
else
{
// User is not logged in
[FBSession openActiveSessionWithAllowLoginUI:YES];
}