如何在计时器结束时自动segue

Question

我想在计时器用完时自动segue。

我在这里构造了一个计时器:

class Timer{
var timer = NSTimer();
// the callback to be invoked everytime the timer 'ticks'
var handler: (Int) -> ();
//the total duration in seconds for which the timer should run to be set by the caller
let duration: Int;
//the amount of time in seconds elapsed so far
var elapsedTime: Int = 0;
var targetController = WaitingRoomController.self

/**
:param: an integer duration specifying the total time in seconds for which the timer should run repeatedly
:param: handler is reference to a function that takes an Integer argument representing the elapsed time allowing the implementor to process elapsed time and returns void
*/
init(duration: Int , handler : (Int) -> ()){
    self.duration = duration;
    self.handler = handler;
}
/**
Schedule the Timer to run every 1 second and invoke a callback method specified by 'selector' in repeating mode
*/
func start(){
    self.timer = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: "onTick", userInfo: nil, repeats: true);
}
/**
invalidate the timer
*/
func stop(){
    println("timer was invaidated from stop()")
    timer.invalidate();
}

/**
Called everytime the timer 'ticks'. Keep track of the total time elapsed and trigger the handler to notify the implementors of the current 'tick'. If the amount of time elapsed is the same as the total duration for the timer was intended to run, stop the timer.
*/

@objc func onTick() {
    //println("onTick")
    //increment the elapsed time by 1 second
    self.elapsedTime++;
    //Notify the implementors of the updated value of elapsed time
    self.handler(elapsedTime);
    //If the amount of elapsed time in seconds is same as the total time in seconds for which this timer was intended to run, stop the timer
    if self.elapsedTime == self.duration {
        self.stop();
    }
}
deinit{
    println("timer was invalidated from deinit()")
    self.timer.invalidate();
}

}

这是我想要执行segue的视图控制器以及计时器是如何开始的

class WaitingRoomController: UIViewController {
    private func handleSetAction(someTime: String){
       countDownLabel.text = setTime;
       let duration = Utils.getTotalDurationInSeconds(someTime);
       timer = Timer(duration: duration ){
          (elapsedTime: Int) -> () in
             println("handler called")
            let difference = duration - elapsedTime;
            self.countDownLabel.text = Utils.getDurationInMinutesAndSeconds(difference)
       }
       timer.start();
    }
}

我知道自动segue的代码是:

func doSegue(){
    self.performSegueWithIdentifier("asdf", sender: self)
}

，但我不知道如何连接定时器和这个功能在一起。

Answer 1

你需要使用闭包来实现你想要的，看看我的类Timer。

import UIKit
class Timer: NSObject {
    var counter: Int = 0
    var timer: NSTimer! = NSTimer()
    var timerEndedCallback: (() -> Void)!
    var timerInProgressCallback: ((elapsedTime: Int) -> Void)!
    func startTimer(duration: Int, timerEnded: () -> Void, timerInProgress: ((elapsedTime: Int) -> Void)!) {
       if !(self.timer?.valid != nil) {
           let aSelector : Selector = "updateTime:"
           timer = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: aSelector, userInfo: duration, repeats: true)
           timerEndedCallback = timerEnded
           timerInProgressCallback = timerInProgress
           counter = 0
       }
    }
    func updateTime(timer: NSTimer) {
       ++self.counter
       let duration = timer.userInfo as! Int
       if (self.counter != duration) {
          timerInProgressCallback(elapsedTime: self.counter)
       } else {
          timer.invalidate()
          timerEndedCallback()
       }
    }
}

然后您可以通过以下方式调用Timer类:

var timer = Timer()
timer.startTimer(5, timerEnded: { () -> Void in
        // Here you call anything you want when the timer finish.
        println("Finished")
        }, timerInProgress: { (elapsedTime) -> Void in
            println("(Int(elapsedTime))")
})

上面的类处理定时器的使用，当它已经有效，并注意到duration参数被传递给updateTime处理程序使用timer参数中的userInfo。

Answer 2

将'selector:"On Tick"'改为'selector:@selctor(doSegue)'。你也可以在这里查看更多关于如何使用NSTimer