Question

我有这段代码可以移动图像，但我想在打开页面后5秒钟显示它。

我该怎么做？谢谢

@IBOutlet weak var moveobj: UIImageView!



override func viewDidAppear(animated: Bool) {


    super.viewDidAppear(animated)


    let orbit = CAKeyframeAnimation(keyPath: "position")
    var affineTransform = CGAffineTransformMakeRotation(0.0)
    affineTransform = CGAffineTransformRotate(affineTransform, CGFloat(M_PI))
    let circlePath = UIBezierPath(arcCenter: CGPoint(x: 198 - (100/2),y: 135 - (100/2)), radius:  CGFloat(155), startAngle: CGFloat(255), endAngle:CGFloat(M_PI * 2 ), clockwise: true)


    orbit.path = circlePath.CGPath
    orbit.duration = 18
    orbit.additive = true
    orbit.repeatCount = 0.15
    orbit.calculationMode = kCAAnimationPaced


    moveobj.layer .addAnimation(orbit, forKey: "orbit")

Answer 1

我不确定你是否在寻找它。除了使用像Rashwan建议的计时器之外，您还可以使用GCD。

在override func viewDidAppear(animated: Bool) { super.viewDidAppear(animated) loadImage() let delayInSeconds = 5.0 let popTime = dispatch_time(DISPATCH_TIME_NOW, Int64(delayInSeconds * Double(NSEC_PER_SEC))) dispatch_after(popTime, dispatch_get_main_queue()) { //You can add some "finish up" operations here } }中显示图片，然后添加以下代码，延迟5秒，如下：

plot(Average.BL~Wet.weight, log="xy")
reg=lm(log(Average.BL)~log(Wet.weight))
abline(reg, untf=FALSE)

Answer 2

要做任何事情之前要等5秒才能使用Timer，请参阅下面的使用方法：

override func viewDidLoad() {
    super.viewDidLoad()

    // start a new timer with an interval of 5 seconds
    Timer.scheduledTimer(timeInterval: 5, target: self, selector: #selector(ViewController.showImage), userInfo: nil, repeats: false)
}

// after 5 seconds this class will be called and here you can do your work
func showImage(){
    print("Showing")
}

显示和移动图像

2 个答案: