如何在iOS 15上使用UIWindowScene.windows

Question

目前，在iOS 14.6中，我可以使用以下代码在应用程序中调用一个显示共享表的函数：

func share(link: URL) {
let activityView = UIActivityViewController(activityItems: [link], applicationActivities: nil)
UIApplication.shared.windows.first?.rootViewController?.present(activityView, animated: true, completion: nil)
}

自从iOS 15测试版以来，Xcode告诉我"'windows’在iOS 15.0中被弃用：在相关的窗口场景上使用UIWindowScene.windows。如何更新此信息，以便我的共享工作表在此新版本中正常工作？谢谢

Answer 1

(使用运行在Xcode 13.2.1上的iOS 15.2进行测试(

改进了Rachid的答案，这里有一个Swiftier版本：

extension UIApplication {

var keyWindow: UIWindow? {
// Get connected scenes
return self.connectedScenes
// Keep only active scenes, onscreen and visible to the user
.filter { $0.activationState == .foregroundActive }
// Keep only the first `UIWindowScene`
.first(where: { $0 is UIWindowScene })
// Get its associated windows
.flatMap({ $0 as? UIWindowScene })?.windows
// Finally, keep only the key window
.first(where: .isKeyWindow)
}

}

如果你想在密钥UIWindow中找到呈现的UIViewController，这里有另一个你可以找到有用的extension：

extension UIApplication {

var keyWindowPresentedController: UIViewController? {
var viewController = self.keyWindow?.rootViewController

// If root `UIViewController` is a `UITabBarController`
if let presentedController = viewController as? UITabBarController {
// Move to selected `UIViewController`
viewController = presentedController.selectedViewController
}

// Go deeper to find the last presented `UIViewController`
while let presentedController = viewController?.presentedViewController {
// If root `UIViewController` is a `UITabBarController`
if let presentedController = presentedController as? UITabBarController {
// Move to selected `UIViewController`
viewController = presentedController.selectedViewController
} else {
// Otherwise, go deeper
viewController = presentedController
}
}

return viewController
}

}

你可以把它放在任何你想放的地方，但我个人把它作为extension添加到UIViewController。

这允许我添加更多有用的扩展，比如更容易地呈现UIViewController的扩展，例如：

extension UIViewController {

func presentInKeyWindow(animated: Bool = true, completion: (() -> Void)? = nil) {
DispatchQueue.main.async {
UIApplication.shared.keyWindow?.rootViewController?
.present(self, animated: animated, completion: completion)
}
}

func presentInKeyWindowPresentedController(animated: Bool = true, completion: (() -> Void)? = nil) {
DispatchQueue.main.async {
UIApplication.shared.keyWindowPresentedController?
.present(self, animated: animated, completion: completion)
}
}

}