ios – 如何在swift中每秒执行一个功能？

我想在我正在开发的游戏中添加一个分数到我的场景顶部.得分将取决于你持续多久,并将每秒增加一次.我在这里先向您的帮助表示感谢！

import SpriteKit

class easyScene: SKScene {
let scrollBarEasyBottom = SKSpriteNode(imageNamed: "scrollBarEasyBottom")
let scrollBarEasyTop = SKSpriteNode(imageNamed: "scrollBarEasyTop")
let ball = SKSpriteNode(imageNamed: "ball")
var origSBEBpositionX = CGFloat(0)
var origSBETpositionX = CGFloat(0)
var maxSBEBX = CGFloat(0)
var SBEBSpeed = 5
var maxSBETX = CGFloat(0)
var SBETSpeed = 5
var score = 0
var timer: NSTimer?

var scoreText = SKLabelNode(fontNamed: "Kailasa")

 override func didMoveToView(view: SKView) {
    println("Easy Scene is the location")
    self.backgroundColor = UIColor.blackColor()
    self.scrollBarEasyBottom.position = CGPoint(x:0,y:270)
    self.addChild(self.scrollBarEasyBottom)
    self.scrollBarEasyBottom.yScale = 0.2
    self.origSBEBpositionX = self.scrollBarEasyBottom.position.x
    // end scrollBarEasyBottom
    self.scrollBarEasyTop.position = CGPoint(x:20,y:400)
    self.addChild(self.scrollBarEasyTop)
    self.scrollBarEasyTop.yScale = 0.2
    self.origSBETpositionX = self.scrollBarEasyTop.position.x
    // end scrollBarEasyTop
    self.ball.position = CGPoint(x:40,y:293)
    self.addChild(self.ball)
    self.ball.yScale = 0.17
    self.ball.xScale = 0.17
    // end ball
    self.maxSBEBX = self.scrollBarEasyBottom.size.width - self.frame.size.width
    self.maxSBEBX *= -1
    self.maxSBETX = self.scrollBarEasyTop.size.width - self.frame.size.width
    self.maxSBETX *= -1
    //
    self.scoreText.text = "0"
    self.scoreText.fontSize = 60
    self.scoreText.position = CGPoint(x: CGRectGetMidX(self.frame),y: 500)
    self.scoreText.text = String(self.score)
    self.addChild(self.scoreText)
    timer = NSTimer.scheduledTimerWithTimeInterval(1,target: self,selector: Selector("scoreIncrease"),userInfo: nil,repeats: true)
    func scoreIncrease (){
        score++
        println(score)
    }


}
override func update(currentTime: NSTimeInterval){
    if self.scrollBarEasyBottom.position.x <= maxSBEBX + 1200 {
        self.scrollBarEasyBottom.position.x = self.origSBEBpositionX
    }
    if self.scrollBarEasyTop.position.x <= maxSBETX + 1200 {
        self.scrollBarEasyTop.position.x = self.origSBETpositionX
    }

    scrollBarEasyBottom.position.x -= CGFloat(self.SBEBSpeed)
    scrollBarEasyTop.position.x -= CGFloat(self.SBETSpeed)
    // moving bars
    var degreeRotation = CDouble(self.SBEBSpeed) * M_PI / 180
    self.ball.zRotation -= CGFloat(degreeRotation)
    //rotate ball


    }


    }

运行此代码之后,我总是得到一个“无法识别的选择器发送到实例错误”.

解决方法

你可以使用这样的一个

var timer = NSTimer()

override func viewDidLoad() {
        scheduledTimerWithTimeInterval()
}

func scheduledTimerWithTimeInterval(){
        // Scheduling timer to Call the function **Countdown** with the interval of 1 seconds
        timer = NSTimer.scheduledTimerWithTimeInterval(1,selector: Selector("updateCounting"),repeats: true)
    }


    func updateCounting(){
        NSLog("counting..")
    }

Swift 3：

var timer = Timer()

override func viewDidLoad() {               // Use for the app's interface
        scheduledTimerWithTimeInterval()
}

override func didMove(to view: SKView) {    // As part of a game
        scheduledTimerWithTimeInterval()
}

func scheduledTimerWithTimeInterval(){
    // Scheduling timer to Call the function **Countdown** with the interval of 1 seconds
    timer = Timer.scheduledTimer(timeInterval: 1,selector: #selector(self.updateCounting),repeats: true)
}

func updateCounting(){
    NSLog("counting..")
}