Is it possible to determine whether ViewController is presented as Modal?

Since modalViewController has been deprecated in iOS 6, here’s a version that works for iOS 5+ and that compiles without warnings.

Objective-C:

- (BOOL)isModal {
    return self.presentingViewController.presentedViewController == self
      || (self.navigationController != nil && self.navigationController.presentingViewController.presentedViewController == self.navigationController)
      || [self.tabBarController.presentingViewController isKindOfClass:[UITabBarController class]];
}

Swift:

var isModal: Bool {
    return self.presentingViewController?.presentedViewController == self
        || (self.navigationController != nil && self.navigationController?.presentingViewController?.presentedViewController == self.navigationController)
        || self.tabBarController?.presentingViewController is UITabBarController
}

Hat tip to Felipe’s answer.