为customView设置背景色无效

Question

我有一个customView，在button-tap之后显示。我的问题是设置.backgroundColor没有任何效果，它只是一个clear背景。

自定义视图：

let wishWishView: WishStackView = {
let v = WishStackView()
v.backgroundColor = .cyan
v.translatesAutoresizingMaskIntoConstraints = false
return v
}()

AddViewButton：

@objc func addWishButtonTapped(){
self.view.addSubview(self.wishWishView)
wishWishView.centerYAnchor.constraint(equalTo: self.view.centerYAnchor).isActive = true
wishWishView.centerXAnchor.constraint(equalTo: self.view.centerXAnchor).isActive = true
}    

WishWishView只是一个简单的UIView，里面有一个StackView

Answer 1

我的猜测是它是一个UIStackView，它不支持有背景色。

您可以在此处阅读更多关于发生这种情况的原因以及可能的解决方案：https://stackoverflow.com/a/34868367/3992237

Answer 2

您的代码完全错误，首先您将视图设置为：

let wishWishView: UIView = {
let v = UIView()
v.backgroundColor = .cyan
v.translatesAutoresizingMaskIntoConstraints = false
return v
}()

现在设置你的stackView，在我的例子中，我在垂直轴上放了2个标签：

let stackView: UIStackView = {
let label1 = UILabel()
label1.text = "Label 1"
label1.textColor = .red
label1.font = UIFont.systemFont(ofSize: 16)
let label2 = UILabel()
label2.text = "Label 2"
label2.textColor = .black
label2.font = UIFont.systemFont(ofSize: 16)
let sV = UIStackView(arrangedSubviews: [label1, label2])
sV.axis = .vertical
sV.distribution = .fillEqually
sV.translatesAutoresizingMaskIntoConstraints = false
return sV
}()

之后设置你的按钮：

let buttonAddView: UIButton = {
let button = UIButton(type: .system)
button.setTitle("Add View", for: .normal)
button.setTitleColor(.white, for: .normal)
button.backgroundColor = .red
button.addTarget(self, action: #selector(addWishButtonTapped), for: .touchUpInside)
button.translatesAutoresizingMaskIntoConstraints = false
return button
}()

在视图中DidLoad添加按钮并设置约束

view.addSubview(buttonAddView)
buttonAddView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor, constant: 20).isActive = true
buttonAddView.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor, constant: -20).isActive = true
buttonAddView.heightAnchor.constraint(equalToConstant: 50).isActive = true
buttonAddView.widthAnchor.constraint(equalToConstant: 120).isActive = true

现在写一个函数，当按钮被点击时，里面有堆栈视图，在你的函数中，你只调用视图的位置，而不调用它的大小。这样写你的函数：

@objc func addWishButtonTapped(){
view.addSubview(self.wishWishView)
wishWishView.centerYAnchor.constraint(equalTo: self.view.centerYAnchor).isActive = true
wishWishView.centerXAnchor.constraint(equalTo: self.view.centerXAnchor).isActive = true
wishWishView.heightAnchor.constraint(equalToConstant: 100).isActive = true
wishWishView.widthAnchor.constraint(equalToConstant: 200).isActive = true
wishWishView.addSubview(stackView)
stackView.topAnchor.constraint(equalTo: wishWishView.topAnchor).isActive = true
stackView.bottomAnchor.constraint(equalTo: wishWishView.bottomAnchor).isActive = true
stackView.leadingAnchor.constraint(equalTo: wishWishView.leadingAnchor, constant: 10).isActive = true
stackView.trailingAnchor.constraint(equalTo: wishWishView.trailingAnchor, constant: -10).isActive = true
}

现在只需更改wishWishView的背景即可自动设置stackView背景，就这样…