Swift 2.0, Protocol, Delegate and "More Accurate" Timer Example using GC

swift-accurate-timer-example.swift

import UIKit
protocol SomethingDelegate {
    func didUpdateSomething(SomethingHelper:SomethingHelper)
}

// Use CADisplayLink for more "averaged" timer interval
class SomethingHelper : NSObject{
    private var timer : CADisplayLink!
    private var currentIntervalInSec = 0;
    var delegate: SomethingDelegate?
    required init(intervalInSec:Double){
        super.init()
        self.timer = CADisplayLink(target: self, selector: Selector("tick"))
        self.timer.frameInterval = Int(intervalInSec * 60.0)
    }
    deinit {
        stop()
    }
    
    func tick(){
        self.delegate?.didUpdateSomething(self)
    }
    
    func start(){
        self.timer.addToRunLoop(NSRunLoop.currentRunLoop(), forMode: NSRunLoopCommonModes)
    }
    
    func stop(){
        self.timer.removeFromRunLoop(NSRunLoop.currentRunLoop(), forMode: NSRunLoopCommonModes)
    }
}

class DetailViewController: UIViewController, SomethingDelegate {

    private var helper = SomethingHelper(intervalInSec: Double(2.0))
    @IBOutlet weak var SomethingView: SomethingView!

    override func viewDidLoad() {
        super.viewDidLoad()
        self.helper.delegate = self;
        self.helper.start()
    }

    func didUpdateSomething(SomethingHelper:SomethingHelper){
        print(NSDate.timeIntervalSinceReferenceDate())
    }
}