检测视图控制器何时进入后台并恢复

我正在实现一个具有以下要求的 ViewController：如果用户在 15 分钟后返回应用程序，则视图应重新加载数据。

我正在考虑使用viewDidDisappear当应用程序进入后台时保存时间戳viewDidAppear用于检查以前保存的值并在需要时刷新，但在应用程序之间切换时不会调用此方法。

我怎样才能以简单的方式解决这个问题？

use UIApplicationDidBecomeActive用于简历和UIApplicationWillResignActive手柄变为背景

SwiftUI

Text("check application state!")
                .onReceive(NotificationCenter.default.publisher(for: UIApplication.willResignActiveNotification)) { _ in
                    print("User received on  willResignActiveNotification!")
                }
                .onReceive(NotificationCenter.default.publisher(for: UIApplication.didBecomeActiveNotification)) { _ in
                    print("User received on  didBecomeActiveNotification!")
                }

Swift 5.x > 以上

override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        NotificationCenter.default.removeObserver(self, name: UIApplication.willResignActiveNotification, object: nil)
        NotificationCenter.default.removeObserver(self, name:  UIApplication.didBecomeActiveNotification, object: nil)
    }

override func viewDidLoad() {
    super.viewDidLoad()
    NotificationCenter.default.addObserver(self, selector: #selector(self.openAndCloseActivity), name: UIApplication.willResignActiveNotification, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(self.openAndCloseActivity), name: UIApplication.didBecomeActiveNotification, object: nil)
}

@objc func openAndCloseActivity(_ notification: Notification)  {
    if notification.name == UIApplication.didBecomeActiveNotification{
        // become active notifictaion
    }else{
        // willResignActiveNotification
    }
    
}

斯威夫特 5.x

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

override func viewDidLoad() {
    super.viewDidLoad()
    
    NotificationCenter.default.addObserver(self, selector: #selector(self.closeActivityController), name: NSNotification.Name.UIApplicationWillResignActive, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(self.openactivity), name: NSNotification.Name.UIApplicationDidBecomeActive, object: nil)
   
    
}

并将该方法处理为

func closeActivityController()  {
    
    
}

func openactivity()  {
    
    //view should reload the data.
}

其他通知类型是

extension NSNotification.Name { 
@available(iOS 4.0, *)
public static let UIApplicationDidEnterBackground: NSNotification.Name

@available(iOS 4.0, *)
public static let UIApplicationWillEnterForeground: NSNotification.Name

public static let UIApplicationDidFinishLaunching: NSNotification.Name

public static let UIApplicationDidBecomeActive: NSNotification.Name

public static let UIApplicationWillResignActive: NSNotification.Name

public static let UIApplicationDidReceiveMemoryWarning: NSNotification.Name

public static let UIApplicationWillTerminate: NSNotification.Name

}