在Swift中使用NSTimer

Question

在这种情况下,永远不会调用timerFunc().我错过了什么？

class AppDelegate: NSObject, NSApplicationDelegate {

    var myTimer: NSTimer? = nil

    func timerFunc() {
        println("timerFunc()")
    }

    func applicationDidFinishLaunching(aNotification: NSNotification?) {
        myTimer = NSTimer(timeInterval: 5.0, target: self, selector:"timerFunc", userInfo: nil, repeats: true)
    }
}

Answer 1

您可以创建一个计划的计时器,它自动将自己添加到runloop并开始触发:

NSTimer.scheduledTimerWithTimeInterval(0.5, target: self, selector: "timerDidFire:", userInfo: userInfo, repeats: true)

或者,您可以保留当前代码,并在准备好时将计时器添加到runloop:

Timer.scheduledTimer(withTimeInterval: 0.5, target: self, selector: #selector(timerDidFire(_:)), userInfo: userInfo, repeats: true)

Answer 2

我对卢克采用了类似的方法.只有对"私人方法"纯粹主义者的警告:

不要在Swift中私有回调.

如果你写:

private func timerCallBack(timer: NSTimer){

..

你会得到:

timerCallBack:]:无法识别的选择器发送到实例...由于未捕获的异常'NSInvalidArgumentException'终止应用程序

Answer 3

除非您使用NSTimer.scheduledTimerWithTimeInterval以下内容,否则不会自动安排NSTimer :

myTimer = NSTimer.scheduledTimerWithTimeInterval(5.0, target: self, selector: "timerFunc", userInfo: nil, repeats: true)

Answer 4

正如Drewag和Ryan指出的那样,你需要创建一个预定的计时器(或自己安排)最简单的方法是创建它已安排好的计划:

myTimer = NSTimer.scheduledTimerWithTimeInterval(5.0, target: self, selector: "timerFunc:", userInfo: nil, repeats: true)

您还需要更改timerFunc(和关联的选择器)的定义以获取参数并以":"结束

func timerFunc(timer:NSTimer!) {
    ...
}

Answer 5

对于Swift 3

var timer = Timer.scheduledTimer(timeInterval: 0.01, target: self, selector: #selector(ViewController.updateTimer), userInfo: nil, repeats: true);
RunLoop.current.add(timer, forMode: RunLoopMode.commonModes)

Answer 6

运行循环的Swift 3.0语法:

RunLoop.current.add(myTimer, forMode: .commonModes)