facebook does not logout properly in ios app.cannot switch users - ios

Question

i am using the facebook login button provided by the fb sdk for implementing the facebook login in my app.When i am logging out the facebook button does change back to login again.but when i click on it,the safari app opens showing "you have alreay authorised the app"click confirm or cancel.Actually i needed the facebook login and password screen here.I cannot switch user until i reset the simulator.how to reset the contents in safari programmatically each time i logout so that the login screen is shown each time.
Please note that when i clear the website data of safari manually it shows the login page again.can it be done programmatically.
code i am using for login is as follows
//creating the login button
FBLoginView *loginView =
[[FBLoginView alloc] initWithReadPermissions:
#[#"public_profile", #"email", #"user_friends"]];
loginView.frame=CGRectMake(50, 500, 225, 55);
loginView.delegate=self;
[self.view addSubview:loginView];
//delegate method when logged in
- (void)loginViewFetchedUserInfo:(FBLoginView *)loginView
user:(id<FBGraphUser>)user {
NSUserDefaults *defaults=[NSUserDefaults standardUserDefaults];
[defaults setObject:[user objectForKey:#"id"] forKey:#"LoggedInUserID"] ;
[self checkandsaveNewUserInBackend:user];
[self performSegueWithIdentifier:#"Login" sender:self];
}
//logout code
- (IBAction)logoutButtonPressed:(id)sender {
[FBSession.activeSession closeAndClearTokenInformation];
[self.navigationController popToRootViewControllerAnimated:YES];
}

Answer 1

try this it user clicks on logout and remove all keys stored in userdefault/cookies
NSLog(#"Logged out facebook");
NSHTTPCookie *cookie;
NSHTTPCookieStorage *storage = [NSHTTPCookieStorage sharedHTTPCookieStorage];
for (cookie in [storage cookies])
{
NSString* domainName = [cookie domain];
NSRange domainRange = [domainName rangeOfString:#"facebook"];
if(domainRange.length > 0)
{
[storage deleteCookie:cookie];
}
}

Answer 2

Try this...
[FBSession.activeSession closeAndClearTokenInformation];
[FBSession.activeSession close];
[FBSession setActiveSession:nil];
May work for you...
And for clear cookies from browser...follow this link \
http://www.iossnippet.com/snippets/web/how-to-delete-cookies-nshttpcookie-in-objective-c-ios/

Answer 3

In the
//logout code
- (IBAction)logoutButtonPressed:(id)sender {
Use following code
if (FBSession.activeSession.state == FBSessionStateOpen
|| FBSession.activeSession.state == FBSessionStateOpenTokenExtended) {
// Close the session and remove the access token from the cache
// The session state handler (in the app delegate) will be called automatically
[FBSession.activeSession closeAndClearTokenInformation];
// If the session state is not any of the two "open" states when the button is clicked
} else {
// Open a session showing the user the login UI
// You must ALWAYS ask for public_profile permissions when opening a session
[FBSession openActiveSessionWithReadPermissions:#[#"public_profile"]
allowLoginUI:YES
completionHandler:
^(FBSession *session, FBSessionState state, NSError *error) {
}];
}