Swift-游戏计时器倒计时

Question

I have looked online at many different 'Timer' tutorials, but they are over-complicated with things like backgrounds etc What I would like is a timer at the top of the screen that counts down '3, 2, 1, Play'. I will have images instead of text. This timer is activated as soon as a touch - to - begin button is clicked (which I have already made). Any help you can give me to do this in Apple Swift would be very greatly appreciated.

Answer 1

Did you try the method scheduledTimerWithTimeInterval from NSTimer

// IBOutlet From Storyboard
@IBOutlet weak var imgView: UIImageView!

var countdown : Int! = 0   // Variable to check the count down seconds

override func viewDidLoad() {
      // Scheduling timer to Call the function **Countdown** with the interval of 1 seconds
      NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: Selector("countDown:"), userInfo: nil, repeats: true)
 }

 func countDown(timer: NSTimer) {
    countdown = countdown + 1   
    if (countdown == 1) {       // second 1, show image 3 
        imgView.image = UIImage(named: "three.png")
    }
    else if (countdown == 2) {  // second 2, show image 2
        imgView.image = UIImage(named: "two.png")
    }
    else if (countdown == 3) {  // second 3, show image 1
        imgView.image = UIImage(named: "one.png")
    }
    else if (countdown == 4) {  // second 4, show image 'play'
        imgView.image = UIImage(named: "play.png")            
    }
    else {
    // Invalidate the timer & remove the `time image` and continue with your `gameplay`
        imgView.removeFromSuperview()
        timer.invalidate()
    }
 }