爆速タイマー

TimerViewController.swift

import UIKit

class TimerViewController: UIViewController {

    @IBOutlet weak var counetrLabel: UILabel!
    var counter: Float = 0.0
    var stepCounter: Int = 0
    var timer: NSTimer?
    
    override func viewDidLoad() {
        super.viewDidLoad()
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }
    
    @IBAction func addtimer(sender: AnyObject) {
        timer = NSTimer.scheduledTimerWithTimeInterval(0.1,
            target: self,
            selector: Selector("updateCounter"),
            userInfo: nil,
            repeats: true
        )
        timer!.fire()
    }

    func updateCounter() {
        counter += 0.1
        self.counetrLabel.text = NSString(format: "%.1f", counter) as String
        if Int(counter) > stepCounter {
            stepCounter = Int(counter)
            println("do something: \(stepCounter)")
        }
    }
}