Unwind segue with Navigation back button

In the end I didn't need to unwind the segue since I could still get a reference to the parent controller methods by following the navigation controller.

I was able to get a reference by doing the following in the - (void)viewWillDisappear:(BOOL)animated method of the child controller

NSInteger currentVCIndex = [self.navigationController.viewControllers indexOfObject:self.navigationController.topViewController];FirstViewController *parent = (FirstViewController *)[self.navigationController.viewControllers objectAtIndex:currentVCIndex];parent.barcodeType = indexPath.row;

which passed the settings variable back to the original controller perfectly.

I also added an import reference to the parent controller at the top of the childcontroller

@Alan is on the right track. Just add a test to prevent the segue from firing when not going back to the first view controller. Something like this in viewWillDisappear will actually allow you to perform the unwind segue for a back button. You will need to create a manual unwind segue by dragging from the class down to the exit icon. Be sure to name it after you create it.

UIViewController *vc = self.navigationController.topViewController;if ([FirstViewController class] == [vc class]){    [self performSegueWithIdentifier:@"unwindSegue" sender:self];}

I'd like to add a Swift solution that follows @Chuck H suggestion above:

let rootVC = self.navigationController!.topViewControllerif rootVC.isKindOfClass(TheNameOfYourViewController) {    performSegueWithIdentifier("yourNamedSegueIdentifier", sender: self)}