How do I get the RootViewController from a pushed controller

Question

So  I push a view controller from RootViewController like     self navigationController pushViewController anotherViewController animated YES      BUT  FROM anotherViewController now  I want to access the RootViewController again   I m trying       inside anotherViewController now     RootViewController  root    RootViewController  self parentViewController      No     err RootViewController  root    RootViewController   self navigationController viewControllers objectAtIndex 0       YES   it works    I m not sure WHY this works and I m not sure if its the best way to do it   Can somebody comment on a better way to get the RootViewController from a controller you ve pushed into that RootViewController s navigationController and whether or not the way I ve done it is reliable or not

User · Answer

This worked for me   When my root view controller is embedded in a navigation controller   UINavigationController   navigationController    UINavigationController       UIApplication sharedApplication  windows  firstObject  rootViewController   RootViewController   rootVC    RootViewController     navigationController viewControllers  firstObject     Remember that keyWindow is deprecated

User · Answer

Use the viewControllers property of the UINavigationController  Example code      Inside another ViewController NSArray  viewControllers   self navigationController viewControllers  UIViewController  rootViewController    viewControllers objectAtIndex viewControllers count - 2     This is the standard way of getting the  back  view controller  The reason objectAtIndex 0 works is because the view controller you re trying to access is also the root one  if you were deeper in the navigation  the back view would not be the same as the root view

User · Answer

Swift version    var rootViewController   self navigationController  viewControllers first   ObjectiveC version    UIViewController  rootViewController    self navigationController viewControllers firstObject     Where self is an instance of a UIViewController embedded in a UINavigationController

User · Answer

A slightly less ugly version of the same thing mentioned in pretty much all these answers   UIViewController  rootViewController     self navigationController viewControllers  firstObject     in your case  I d probably do something like   inside your UINavigationController subclass   -  UIViewController   rootViewController       return   self viewControllers  firstObject       then you can use   UIViewController  rootViewController    self navigationController rootViewController     edit  OP asked for a property in the comments   if you like  you can access this via something like self navigationController rootViewController by just adding a readonly property to your header    property  nonatomic  readonly  weak  UIViewController  rootViewController

User · Answer

For all who are interested in a swift extension  this is what I m using now   extension UINavigationController       var rootViewController   UIViewController            return self viewControllers first

User · Answer

How about asking the UIApplication singleton for its keyWindow  and from that UIWindow ask for the root view controller  its rootViewController property    UIViewController root      UIApplication sharedApplication  keyWindow  rootViewController

User · Answer

As an addition to  dulgan s answer  it is always a good approach to use firstObject over objectAtIndex 0  because while first one returns nil if there is no object in the array  latter one throws exception   UIViewController  rootViewController   self navigationController rootViewController    Alternatively  it d be a big plus for you to create a category named UINavigationController Additions and define your method in that    interface UINavigationController  Additions   -  UIViewController   rootViewController    end   implementation UINavigationController  Additions   -  UIViewController   rootViewController       return self viewControllers firstObject      end

User · Answer

Here I came up with universal method to navigate from any place to root    You create a new Class file with this class  so that it s accessible from anywhere in your project   import UIKit  class SharedControllers       static func navigateToRoot viewController  UIViewController                var nc   viewController navigationController             If this is a normal view with NavigationController  then we just pop to root          if nc    nil                       nc  popToRootViewControllerAnimated true              return                       Most likely we are in Modal view  so we will need to search for a view with NavigationController          let vc   viewController presentingViewController          if nc    nil                       nc   viewController presentingViewController  navigationController                    if nc    nil                       nc   viewController parentViewController  navigationController                    if vc is UINavigationController  amp  amp  nc    nil                       nc   vc as  UINavigationController                    if nc    nil                       viewController dismissViewControllerAnimated false  completion                                        nc  popToRootViewControllerAnimated true                                    Usage from anywhere in your project                 SharedControllers navigateToRoot self

User · Answer

I encounter a strange condition  self viewControllers first is not root viewController always  Generally  self viewControllers first is root viewController indeed  But sometimes it s not  class MyCustomMainNavigationController  UINavigationController        function configureForView   v  UIViewController  animated  Bool            let root   self viewControllers first         let isRoot    v    root                  Update UI based on isRoot                          extension MyCustomMainNavigationController  UINavigationControllerDelegate       func navigationController   navigationController  UINavigationController           willShow viewController  UIViewController           animated  Bool             self configureForView viewController  animated  animated           My issue  Generally  self viewControllers first is root viewController  But  when I call popToRootViewController animated    and then it triggers navigationController   willShow animated    At this moment  self viewControllers first is NOT root viewController  it s the last viewController which will disappear  Summary  self viewControllers first is not always root viewController   Sometime  it will be the last viewController   So  I suggest to keep rootViewController by property when self viewControllers have ONLY one viewController  I get root viewController in viewDidLoad   of custom UINavigationController  class MyCustomMainNavigationController  UINavigationController       fileprivate var myRoot  UIViewController      override func viewDidLoad              super viewDidLoad               My UINavigationController is defined in storyboard              So at this moment              I can get root viewController by  self topViewController           let v   self topViewController          self myRoot   v           Enviroments   iPhone 7 with iOS 14 0 1 Xcode 12 0 1  12A7300

[ios] How do I get the RootViewController from a pushed controller?

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