Get top most UIViewController

Question

I can\'t seem to get the top most UIViewController without access to a UINavigationController. Here is what I have so far:

UIApplic         


        

Answer 1

In a very rare case, with custom segue, the top most view controller is not in a navigation stack or tab bar controller or presented, but its view is inserted to the top of key windown's subviews.

In such situation, it's necessary to check if UIApplication.shared.keyWindow.subviews.last == self.view to determine if the current view controller is the top most.

Answer 2

iOS13+ //top Most view Controller

extension UIViewController {
    func topMostViewController() -> UIViewController {
        if self.presentedViewController == nil {
            return self
        }
        if let navigation = self.presentedViewController as? UINavigationController {
            return navigation.visibleViewController!.topMostViewController()
        }
        if let tab = self.presentedViewController as? UITabBarController {
            if let selectedTab = tab.selectedViewController {
                return selectedTab.topMostViewController()
            }
            return tab.topMostViewController()
        }
        return self.presentedViewController!.topMostViewController()
    }
}

extension UIApplication {
    func topMostViewController() -> UIViewController? {
        return UIWindow.key!.rootViewController?.topMostViewController()
    }
}

extension UIWindow {
    static var key: UIWindow? {
        if #available(iOS 13, *) {
            return UIApplication.shared.windows.first { $0.isKeyWindow }
        } else {
            return UIApplication.shared.keyWindow
        }
    }
}

//use let vc = UIApplication.shared.topMostViewController()

// End top Most view Controller

Answer 3

class func topViewController(controller: UIViewController? = UIApplication.shared.keyWindow?.rootViewController) -> UIViewController? {
        if let navigationController = controller as? UINavigationController {
            return topViewController(controller: navigationController.visibleViewController)
        }
        if let tabController = controller as? UITabBarController {
            if let selected = tabController.selectedViewController {
                return topViewController(controller: selected)
            }
        }
        if let presented = controller?.presentedViewController {
            return topViewController(controller: presented)
        }
        return controller
    }

Answer 4

I loved @dianz's answer, and so here is the swift 3's version of it. It's basically the same thing but his was missing a curly brace and some of the syntax/variable/method names have changed. So here it is!

extension UIApplication {
    class func topViewController(base: UIViewController? = UIApplication.shared.keyWindow?.rootViewController) -> UIViewController? {
        if let nav = base as? UINavigationController {
            return topViewController(base: nav.visibleViewController)
        }
        if let tab = base as? UITabBarController {
            if let selected = tab.selectedViewController {
                return topViewController(base: selected)
            }
        }
        if let presented = base?.presentedViewController {
            return topViewController(base: presented)
        }
        return base
    }
}

Usage is still the exact same though:

if let topController = UIApplication.topViewController() {
    print("The view controller you're looking at is: \(topController)")
}

Answer 5

To find the visible viewController in Swift 3

if let viewControllers = window?.rootViewController?.childViewControllers {

     let prefs = UserDefaults.standard

     if viewControllers[viewControllers.count - 1] is ABCController{
        print("[ABCController] is visible")

     }
}

This code find the last added or the last active controller visible.

This I have used in AppDelegate to find active view Controller

Answer 6

presentViewController shows a view controller. It doesn't return a view controller. If you're not using a UINavigationController, you're probably looking for presentedViewController and you'll need to start at the root and iterate down through the presented views.

if var topController = UIApplication.sharedApplication().keyWindow?.rootViewController {
    while let presentedViewController = topController.presentedViewController {
        topController = presentedViewController
    }

    // topController should now be your topmost view controller
}

For Swift 3+:

if var topController = UIApplication.shared.keyWindow?.rootViewController {
    while let presentedViewController = topController.presentedViewController {
        topController = presentedViewController
    }

    // topController should now be your topmost view controller
}

For iOS 13+

let keyWindow = UIApplication.shared.windows.filter {$0.isKeyWindow}.first

if var topController = keyWindow?.rootViewController {
    while let presentedViewController = topController.presentedViewController {
        topController = presentedViewController
    }

// topController should now be your topmost view controller
}