swift - 看不到 UIView 的 UIView subview

Question

我看不到添加到 UIView 的 UIView subview 。我可以在 View 层次结构中清楚地看到它，但我在应用程序运行时看不到它。

代码:

var magnifyingView: UIView = {
    let view = UIView()
    view.alpha = 1.0
    view.backgroundColor = UIColor.yellow
    return view
}()

guard let cgImage = capturedImage else{return}
    let image = UIImage.init(cgImage: cgImage, scale: 1.0, orientation: UIImage.Orientation.right)
    imageView.image = image
    self.addSubview(imageView)
    bottomSection.addSubview(homeButton)
    bottomSection.addSubview(retakeButton)
    bottomSection.addSubview(continueButton)
    self.addSubview(bottomSection)

    showMagifyingView()
    self.bringSubviewToFront(magnifyingView)

private func showMagifyingView(){
    magnifyingView = UIView()
    magnifyingView.frame = CGRect.init(x: 30, y: 30, width: 200, height: 200)
    self.addSubview(magnifyingView)

    magnifyingView.translatesAutoresizingMaskIntoConstraints = false
    magnifyingView.widthAnchor.constraint(equalTo: self.widthAnchor, multiplier: 0.3).isActive = true
    magnifyingView.heightAnchor.constraint(equalTo: self.widthAnchor, multiplier: 0.3).isActive = true
    magnifyingView.topAnchor.constraint(equalTo: self.topAnchor, constant: 30).isActive = true
    magnifyingView.trailingAnchor.constraint(equalTo: self.trailingAnchor, constant: -30).isActive = true

}

View Heirarchy(蓝色突出显示的矩形 UIview 是我在运行时在我的应用程序上看不到的内容。即使它在那里并且我已将它放在前面)

Answer 1

在类的顶部初始化magnifyingView

var magnifyingView: UIView = {
    let view = UIView()
    view.alpha = 1.0
    view.backgroundColor = UIColor.yellow
    return view
}()

但是您要在 showMagifyingView() 中添加一个不同的 magnifyingView = UIView() 作为 subview 。