Changing score with a delay - swift

Question

I want to create this effect, that the score is changing with a delay between every number, like the score on the game over screen in Flappy Bird.
In this example, it should start counting when I touch the screen.
import SpriteKit
class GameScene: SKScene, SKPhysicsContactDelegate {
// Global declaration of objects
var scoreLabel = SKLabelNode()
var score:Int = 15
override func didMoveToView(view: SKView) {
/* Setup your scene here */
scoreLabel = SKLabelNode(fontNamed: "RubberBiscuitBold")
scoreLabel.fontSize = 50
scoreLabel.fontColor = SKColor.blackColor()
scoreLabel.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame))
scoreLabel.zPosition = 1000
self.addChild(scoreLabel)
}
override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
/* Called when a touch begins */
for var i = 0; i <= score; i++ {
scoreLabel.runAction(SKAction.waitForDuration(1))
scoreLabel.text = "\(i)"
print("\(i)")}
}

Answer 1

try something like this:
for var i = 0; i <= 10; i++ {
let seconds: Double = 0.5
let count = i
let delay = seconds * Double(NSEC_PER_SEC) // nanoseconds per seconds
let dispatchTime = dispatch_time(DISPATCH_TIME_NOW, Int64(delay * Double(i)))
dispatch_after(dispatchTime, dispatch_get_main_queue(), {
print("\(count)")
scoreLabel.text = "\(count)" })
}

Answer 2

Alternatively, with a recursive function definition it gets a bit more compact (and hopefully usable)
func countUp(start: Int, end: Int, delay: Double) {
if start <= end {
let del = delay * Double(NSEC_PER_SEC)
let time = dispatch_time(DISPATCH_TIME_NOW, Int64(del))
dispatch_after(time, dispatch_get_main_queue()) {
print("\(start)") // Your rendering code here
countUp(start + 1, end: end, delay: delay)
}
} else {
let del = delay * Double(NSEC_PER_SEC)
let time = dispatch_time(DISPATCH_TIME_NOW, Int64(del))
dispatch_after(time, dispatch_get_main_queue()) {
print("I'm done!") // Your continuation code here
// Please not that you should, for clarity and maintenance, wrap your delayed execution code inside a function.....
}
}
}
countUp(10, end: 20, delay: 1)

Answer 3

Just an idea here.
What if you create an additional node between the pipes that are a bit smaller.
Make it so that once they collide it ups your score.
That would also bring you the delay you want.