为什么我的uiimageview框架没有更新？

Question

我有IBOutlet imageProfile（UIImageView）。 当我在代码中设置框架时，我的UIImageView框架未更新，但我的图层已更新， 你能告诉我为什么吗？

@IBOutlet weak var imageProfile: UIImageView!

override func viewDidLoad() {

    super.viewDidLoad()
    setDesign()

 }

func setDesign() {
        var newFrame=imageProfile.frame
    newFrame.origin.x=50
    newFrame.origin.y=100
    newFrame.size.width=150
    newFrame.size.height=150
    imageProfile.frame=newFrame
    imageProfile.layer.borderColor = UIColor.whiteColor().CGColor
    imageProfile.backgroundColor=UIColor.blackColor()
    imageProfile.layer.cornerRadius = 75
    imageProfile.layer.borderWidth=3
    imageProfile.clipsToBounds = true
    imageProfile.updateConstraints()


}

如果我删除IBOutlet并尝试此操作，我的框架会更新：

var imageProfile: UIImageView?
override func viewDidLoad() {

super.viewDidLoad()
setDesign()

}
  func setDesign() {
    var image: UIImage = UIImage(named: "iconSuggestSelect.png")!
    imageProfile = UIImageView(image: image)
    imageProfile!.frame = CGRectMake(100,100,100,200)
    imageProfile!.layer.borderColor = UIColor.whiteColor().CGColor
    imageProfile!.backgroundColor=UIColor.blackColor()
    imageProfile!.layer.cornerRadius = 75
    imageProfile!.layer.borderWidth=3
    imageProfile!.clipsToBounds = true
    imageProfile!.updateConstraints()
    imageCover.addSubview(imageProfile!)

}