Q:

FB iOS SDK - How to detect when user tap done?

I wonder how to detect when user tap Done in upper left corner to skip sign in. 
Is any delegate method being called at that moment?
I need to detect that to unlock userInteraction in my UI.

A:

FBSDKLoginManager *login = [[FBSDKLoginManager alloc] init];
[login logInWithReadPermissions: @[PERMISSIONS] fromViewController:self handler:^(FBSDKLoginManagerLoginResult *result, NSError *error) {
    if (error) {
        NSLog(@"Process error %@", error);
    } else if (result.isCancelled) {
      // User tap Done
    } else {
      // Successful login  
    }
}];

