ios - 从特定的 UIViewController 识别 applicationDidBecomeActive

Question

我想知道有没有一种方式或方法可以用来操作一段代码，当应用程序从后台调用并激活时。我需要从 View 本身而不是应用程序委托(delegate)中工作的方法

Answer 1

当您需要在 View Controller 中执行某些操作以从后台唤醒时，您必须使用 UIApplicationDidBecomeActiveNotification 的监听器

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    NotificationCenter.default.addObserver(self, selector: #selector(self.executeMethod), name: NSNotification.Name.UIApplicationDidBecomeActive, object: nil)
}

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)
    NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIApplicationDidBecomeActive, object: nil)
}

func executeMethod()  {
    // execute your code here
}