check this ...
- (void)sessionStateChanged:(FBSession *)session
state:(FBSessionState) state
error:(NSError *)error {
switch (state) {
case FBSessionStateOpen:
if (!error) {
// We have a valid session
NSLog(@" Info : Valid FBSession found...");
[self fetchFacebookUserInfo];
}
break;
case FBSessionStateClosed:
case FBSessionStateClosedLoginFailed: {
NSLog(@" Info : No Valid FBSession found***");
}
break;
default:
break;
}
}
- (void)fetchFacebookUserInfo {
if ([self sessionIsOpen]) {
[FBRequestConnection startForMeWithCompletionHandler:^(FBRequestConnection *connection,
id<FBGraphUser> user,
NSError *error) {
if (!error) {
NSLog(@"Username %@",user.name);
NSLog(@"Email %@",[user objectForKey:@"email"]);
}
}
}