我如何显示图像

Question

如何在打开页面和此移动后5秒自动显示图像？

我有这段代码，我打开一个页面后5秒钟自动显示图像，但不动就是为什么。

class yourViewController: UIViewController{

 @IBOutlet weak var moveobj: UIImageView!

override func viewDidLoad(){
     super.viewDidLoad()
     moveobj.hidden = true
     moveobj.alpha = 0
     NSTimer.scheduledTimerWithTimeInterval(5, target: self, selector: #selector(UIViewController.showMyBtn), userInfo: nil, repeats: false) 
   }

  func showMyBtn(){
         UIView.animateWithDuration(1, animations: {

        self.moveobj.hidden = false
        self.moveobj.alpha = 1
        })

     }

}
  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 = 3
        orbit.additive = true
        orbit.repeatCount = 0.2
        orbit.calculationMode = kCAAnimationPaced


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