添加自动布局约束后，NIB 中的 UIView 不符合父约束

Question

我正在使用以下方法将我的 NIB 文件加载到我的视图中：

override init(frame: CGRect) {        
    super.init(frame: frame)
    Bundle.main.loadNibNamed("EventPopup", owner: self, options: nil)
    //self.frame = self.view.bounds - DIDN'T WORK
    //self.frame.size.width = 300 - DID'T WORK
    self.addSubview(self.view);    // adding the top level view to the view hierarchy
}

required init(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)!
    Bundle.main.loadNibNamed("EventPopup", owner: self, options: nil)
    self.addSubview(self.view);    // adding the top level view to the view hierarchy
}

这有效并添加了我的 NIB，但 UIView 的宽度延伸到父容器之外。这仅在将自动布局添加到 uiview 后发生。我检查过，初始帧大小为 600x600。

即使在尝试通过调用 layoutSubviews() 来重置 NIB 大小并将新的框架约束放入其中之后，仍然拒绝调整大小。例如：

override func layoutSubviews() {
   // self.frame.size.width = 300
    //self.frame = CGRect(x: self.frame.origin.x, y: self.frame.origin.y, width: 200, height: self.frame.height)
}

Answer 1

看看这个帖子here。查看第三个技巧，它展示了如何创建从 nib 加载的视图。代码转载如下（免责声明它是用 Swift 2 编写的）：

@IBDesignable
class ProfileView: UIView {
   @IBOutlet var imgView: UIImageView!
   @IBOutlet var labelOne: UILabel!
   @IBOutlet var labelTwo: UILabel!
   override init(frame: CGRect) {
      super.init(frame: frame)
      setUp()
   }
   required init?(coder aDecoder: NSCoder) {
      super.init(coder: aDecoder)
      setUp()
   }
   func setUp() {
      let bundle = NSBundle(forClass: self.dynamicType)
      let nib = UINib(nibName: “Profile”, bundle: bundle)
      let viewFromNib = nib.instantiateWithOwner(self, options: nil)[0] as! UIView
      addSubview(viewFromNib)
      viewFromNib.translatesAutoresizingMaskIntoConstraints = false
      self.addConstraints(
         NSLayoutConstraint.constraintsWithVisualFormat(
            “H:|[v]|”, 
            options: NSLayoutFormatOptions(rawValue: 0), 
            metrics: nil, 
            views: [“v”:viewFromNib]
         )
      )
      self.addConstraints(
         NSLayoutConstraint.constraintsWithVisualFormat(
            “V:|[v]|”, 
            options: NSLayoutFormatOptions(rawValue: 0), 
            metrics: nil, views: [“v”:viewFromNib]
         )
      )
   }
}

一旦您在代码和笔尖中正确设置了它，您应该能够轻松地对其进行初始化。在界面生成器或代码中：

// 视图控制器

override viewDidLoad() {
    super.viewDidLoad()
    self.addSubview(ProfileView(frame: CGRect(x: 0, y: 0, width: 100, height: 100)))
}