我试着

var timer = NSTimer()
timer(timeInterval: 0.01, target: self, selector: update, userInfo: nil, repeats: false)

但是,我得到了一个错误

'(timeInterval: $T1, target: ViewController, selector: () -> (), userInfo: NilType, repeats: Bool) -> $T6' is not identical to 'NSTimer'

当前回答

我试着在一个NSObject类,这为我工作:

DispatchQueue.main.asyncAfter(deadline: .now() + .milliseconds(300)) {  
print("Bang!") }

其他回答

斯威夫特5

我个人更喜欢带块闭包的定时器:

    Timer.scheduledTimer(withTimeInterval: 1, repeats: false) { (_) in
       // TODO: - whatever you want
    }

在Swift 4.2中,NSTimer被重命名为Timer。 这个语法将在4.2中工作:

let timer = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(UIMenuController.update), userInfo: nil, repeats: true)
timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(createEnemy), userInfo: nil, repeats: true)

通过createEnemy这个名字创造乐趣

fund createEnemy ()
{
do anything ////
}

首先声明你的计时器

var timer: Timer?

然后在viewDidLoad()或任何你想要启动计时器的函数中添加line

timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(action), userInfo: nil, repeats: false)

这是func,你将回调它来做一些事情它必须是@objc

@objc func action () {
print("done")
}

在iOS 10中,还有一个新的基于块的定时器工厂方法,它比使用选择器更干净:

    _ = Timer.scheduledTimer(withTimeInterval: 5, repeats: false) { timer in
        label.isHidden = true
    }