I have 2 seperate navigationcontrollers, one with RootViewController A and the other with RootViewController B.
I am able to push ViewController C onto either A or B's navigation stack.
Question: When I am in ViewController C, how can I find out if I am in the stack belonging to A or B?
- (UIViewController *)backViewController
{
NSInteger myIndex = [self.navigationController.viewControllers indexOfObject:self];
if ( myIndex != 0 && myIndex != NSNotFound ) {
return [self.navigationController.viewControllers objectAtIndex:myIndex-1];
} else {
return nil;
}
}
My extension, swift 3
extension UIViewController {
var previousViewController: UIViewController? {
guard let controllers = navigationController?.viewControllers, controllers.count > 1 else { return nil }
switch controllers.count {
case 2: return controllers.first
default: return controllers.dropLast(2).first
}
}
}