applicationWillResignActive解散键盘iPhone

Question

在使用我的应用程序期间收到短信时，我希望任何打开的键盘都被驳回。我如何在app委托中从applicationWillResignActive中做到这一点?

Answer 1

实现这个答案中的示例代码。让你的视图控制器注册UIApplicationWillResignActiveNotification。当通知触发时，呼叫resignFirstResponder。这样你就避免了UIApplicationDelegate和视图控制器之间的紧密耦合。假设你的视图控制器有一个名为textField的UITextField:

- (void) applicationWillResign {
    [self.textField resignFirstResponder];
}
- (void) viewDidLoad { 
    [[NSNotificationCenter defaultCenter]
        addObserver:self
        selector:@selector(applicationWillResign)
        name:UIApplicationWillResignActiveNotification 
        object:NULL];
}

Answer 2

对于Swift 5的实现，试试这个

override func viewDidLoad() {
    super.viewDidLoad()
    let notificationCenter = NotificationCenter.default
    notificationCenter.addObserver(self, selector: #selector(appMovedToBackground), name: UIApplication.willResignActiveNotification, object: nil)
}
@objc func appMovedToBackground() {
    print("App moved to background!")
}

更多信息请访问https://www.hackingwithswift.com/example-code/system/how-to-detect-when-your-app-moves-to-the-background