NO
override func willMove(toParentViewController parent: UIViewController?) { }
This will get called even if you are segueing to the view controller in which you are overriding this method. In which check if the "parent" is nil of not is not a precise way to be sure of moving back to the correct UIViewController. To determine exactly if the UINavigationController is properly navigating back to the UIViewController that presented this current one, you will need to conform to the UINavigationControllerDelegate protocol.
YES
note: MyViewController is just the name of whatever UIViewController you want to detect going back from.
1) At the top of your file add UINavigationControllerDelegate.
class MyViewController: UIViewController, UINavigationControllerDelegate {
2) Add a property to your class that will keep track of the UIViewController that you are segueing from.
class MyViewController: UIViewController, UINavigationControllerDelegate {
var previousViewController:UIViewController
3) in MyViewController's viewDidLoad method assign self as the delegate for your UINavigationController.
override func viewDidLoad() {
super.viewDidLoad()
self.navigationController?.delegate = self
}
3) Before you segue, assign the previous UIViewController as this property.
// In previous UIViewController
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "YourSegueID" {
if let nextViewController = segue.destination as? MyViewController {
nextViewController.previousViewController = self
}
}
}
4) And conform to one method in MyViewController of the UINavigationControllerDelegate
func navigationController(_ navigationController: UINavigationController, willShow viewController: UIViewController, animated: Bool) {
if viewController == self.previousViewController {
// You are going back
}
}