SecondViewController.swift

class SecondViewController: UIViewController {
    
    var isPresented = true // This property is very important, set it to true initially
    
    @IBAction
    func dismiss() {
        
        isPresented = false // Set this flag to NO before dismissing controller, so that correct orientation will be chosen for the bottom controller
        self.presentingViewController!.dismissViewControllerAnimated(true, completion: nil);
    }

}