iOS， subview 大小无故改变

Question

 @objc class SearchViewController: UIViewController {

     var uiView: UIView!

     @IBOutlet weak var reactWrapperView: UIView!

     override func viewDidLoad() {
         super.viewDidLoad()


         self.view.layer.borderColor = UIColor.yellow.cgColor
         self.view.layer.borderWidth = 2

         self.reactWrapperView.frame = (self.reactWrapperView.superview?.bounds)!
         self.reactWrapperView.layer.borderColor = UIColor.red.cgColor
         self.reactWrapperView.layer.borderWidth = 5

         self.uiView = UIView(frame: (self.reactWrapperView.superview?.bounds)!)
         self.uiView.layer.borderColor = UIColor.blue.cgColor
         self.uiView.layer.borderWidth = 10

         self.reactWrapperView.addSubview(self.uiView)

     }
 }

self.view 和 self.rectWrapperView 在 Storyboard中创建，它们的大小与手机屏幕相同，如下图所示。

self.view : yellow
self.reactWrapperView : red
self.uiView: blue

如您所见，底部蓝色边框未显示，并且 uiView 似乎变大了。

我已经挣扎了很长时间，想知道什么会影响大小。

Answer 1

您的Viewcontroller UI未更新(意味着未完全加载)，您可以移入主线程或将代码移至viewwillappear或viewDidAppear强>，原因 ui 没有更新。

选项1

override func viewDidLoad() {
         super.viewDidLoad()

         DispatchQueue.main.async { // or use sync


         self.view.layer.borderColor = UIColor.yellow.cgColor
         self.view.layer.borderWidth = 2

         self.reactWrapperView.frame = (self.reactWrapperView.superview?.bounds)!
         self.reactWrapperView.layer.borderColor = UIColor.red.cgColor
         self.reactWrapperView.layer.borderWidth = 5

         self.uiView = UIView(frame: (self.reactWrapperView.superview?.bounds)!)
         self.uiView.layer.borderColor = UIColor.blue.cgColor
         self.uiView.layer.borderWidth = 10

         self.reactWrapperView.addSubview(self.uiView)

     }
    }
 }

选项2

 override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)


         self.view.layer.borderColor = UIColor.yellow.cgColor
         self.view.layer.borderWidth = 2

         self.reactWrapperView.frame = (self.reactWrapperView.superview?.bounds)!
         self.reactWrapperView.layer.borderColor = UIColor.red.cgColor
         self.reactWrapperView.layer.borderWidth = 5

         self.uiView = UIView(frame: (self.reactWrapperView.superview?.bounds)!)
         self.uiView.layer.borderColor = UIColor.blue.cgColor
         self.uiView.layer.borderWidth = 10

         self.reactWrapperView.addSubview(self.uiView)

     }
 }