我正在尝试使用以下代码为 UIApplication.didBecomeActiveNotification 添加观察者:

NotificationCenter.default.addObserver(forName: UIApplication.didBecomeActiveNotification, object: nil, queue: nil) { _ in /* some code */ }

但是 Xcode 说 Type 'UIApplication' has no member 'didBecomeActiveNotification' 尽管它是 officially documented 作为 UIApplication 类常量。我做错了什么?

最佳答案

当您使用 Xcode 10 时,在 build设置 中,如果您将 Swift 语言版本 设置为 Swift 4 ,则应编写:

NotificationCenter.default.addObserver(forName: .UIApplicationDidBecomeActive, object: nil, queue: nil) { _ in /* some code */ }

如果它设置为 Swift 4.2 ,请改用它:
NotificationCenter.default.addObserver(forName: UIApplication.didBecomeActiveNotification, object: nil, queue: nil) { _ in /* some code */ }

关于ios - 类型 'UIApplication' 没有成员 'didBecomeActiveNotification',我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/51570341/

10-13 21:27