How to get visible viewController from app delegate when using storyboard?

This should do it for you:

- (void)applicationWillResignActive:(UIApplication *)application{    UIViewController *vc = [self visibleViewController:[UIApplication sharedApplication].keyWindow.rootViewController];}- (UIViewController *)visibleViewController:(UIViewController *)rootViewController{    if (rootViewController.presentedViewController == nil)    {        return rootViewController;    }    if ([rootViewController.presentedViewController isKindOfClass:[UINavigationController class]])    {        UINavigationController *navigationController = (UINavigationController *)rootViewController.presentedViewController;        UIViewController *lastViewController = [[navigationController viewControllers] lastObject];        return [self visibleViewController:lastViewController];    }    if ([rootViewController.presentedViewController isKindOfClass:[UITabBarController class]])    {        UITabBarController *tabBarController = (UITabBarController *)rootViewController.presentedViewController;        UIViewController *selectedViewController = tabBarController.selectedViewController;        return [self visibleViewController:selectedViewController];    }    UIViewController *presentedViewController = (UIViewController *)rootViewController.presentedViewController;    return [self visibleViewController:presentedViewController];}

@aviatorken89's answer worked well for me. I had to translate it to Swift - for anybody starting out with Swift:

Updated for Swift 3:

func getVisibleViewController(_ rootViewController: UIViewController?) -> UIViewController? {    var rootVC = rootViewController    if rootVC == nil {        rootVC = UIApplication.shared.keyWindow?.rootViewController    }    if rootVC?.presentedViewController == nil {        return rootVC    }    if let presented = rootVC?.presentedViewController {        if presented.isKind(of: UINavigationController.self) {            let navigationController = presented as! UINavigationController            return navigationController.viewControllers.last!        }        if presented.isKind(of: UITabBarController.self) {            let tabBarController = presented as! UITabBarController            return tabBarController.selectedViewController!        }        return getVisibleViewController(presented)    }    return nil}

Old answer:

func applicationWillResignActive(application: UIApplication) {    let currentViewController = getVisibleViewController(nil)}func getVisibleViewController(var rootViewController: UIViewController?) -> UIViewController? {    if rootViewController == nil {        rootViewController = UIApplication.sharedApplication().keyWindow?.rootViewController    }    if rootViewController?.presentedViewController == nil {        return rootViewController    }    if let presented = rootViewController?.presentedViewController {        if presented.isKindOfClass(UINavigationController) {            let navigationController = presented as! UINavigationController            return navigationController.viewControllers.last!        }        if presented.isKindOfClass(UITabBarController) {            let tabBarController = presented as! UITabBarController            return tabBarController.selectedViewController!        }        return getVisibleViewController(presented)    }    return nil}

We implemented it as an UIApplication extension:

import UIKitextension UIApplication {    var visibleViewController: UIViewController? {        guard let rootViewController = keyWindow?.rootViewController else {            return nil        }        return getVisibleViewController(rootViewController)    }    private func getVisibleViewController(_ rootViewController: UIViewController) -> UIViewController? {        if let presentedViewController = rootViewController.presentedViewController {            return getVisibleViewController(presentedViewController)        }        if let navigationController = rootViewController as? UINavigationController {            return navigationController.visibleViewController        }        if let tabBarController = rootViewController as? UITabBarController {            return tabBarController.selectedViewController        }        return rootViewController    }}