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
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 ////
}
其他回答
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Swift 3中使用@objc:
func startTimerForResendingCode() {
let timerIntervalForResendingCode = TimeInterval(60)
Timer.scheduledTimer(timeInterval: timerIntervalForResendingCode,
target: self,
selector: #selector(timerEndedUp),
userInfo: nil,
repeats: false)
}
@objc func timerEndedUp() {
output?.timerHasFinishedAndCodeMayBeResended()
}
这是可行的:
override func viewDidLoad() {
super.viewDidLoad()
// Swift block syntax (iOS 10+)
let timer = Timer(timeInterval: 0.4, repeats: true) { _ in print("Done!") }
// Swift >=3 selector syntax
let timer = Timer.scheduledTimer(timeInterval: 0.4, target: self, selector: #selector(self.update), userInfo: nil, repeats: true)
// Swift 2.2 selector syntax
let timer = NSTimer.scheduledTimerWithTimeInterval(0.4, target: self, selector: #selector(MyClass.update), userInfo: nil, repeats: true)
// Swift <2.2 selector syntax
let timer = NSTimer.scheduledTimerWithTimeInterval(0.4, target: self, selector: "update", userInfo: nil, repeats: true)
}
// must be internal or public.
@objc func update() {
// Something cool
}
对于Swift 4，你想要获取选择器的方法必须暴露在Objective-C中，因此@objc属性必须添加到方法声明中。
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 ////
}
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
}
