UIWindow Presentation Context

Get top most presented UIViewController of UIWindow

There are times when we need to get top most presented UIViewController. We can do so with help of an extension of UIWindow. Consider the following code:

// https://hashaam.com/2017/08/31/uiwindow-presentation-context/
extension UIWindow {
func presentationContext(context: UIViewController? = nil) -> UIViewController? {
var presentationContextViewController = rootViewController
if let context = context {
presentationContextViewController = context
}
if presentationContextViewController?.presentedViewController == nil {
if let navigationController = presentationContextViewController as? UINavigationController {
return navigationController.topViewController
}
return presentationContextViewController
}
return presentationContext(context: presentationContextViewController?.presentedViewController)
}
}

Then we can call using:

// https://hashaam.com/2017/08/31/uiwindow-presentation-context/
if let delegate = UIApplication.shared.delegate, let window = delegate.window, let viewController = window?.presentationContext() {
// perform action on viewController
}