UIView 边框宽度不可见答案

【问题标题】：UIView borderWidth not visibleUIView 边框宽度不可见
【发布时间】：2017-07-05 07:17:29
【问题描述】：

我想要一个带有黑色中心和彩色边框的圆形视图。当我这样设置视图时：

myView.backgroundColor = UIColor.red
myView.layer.borderColor = UIColor.white.cgColor
myView.layer.borderWidth = 3

我只得到一个红色的圆。但是当我转到 Debug View Hierarchy 时，我看到 myView 有一个白色边框。疯狂！我做错了什么？

iPhone：和调试视图层次结构：

【问题讨论】：

有意思，试试把这行myView.layer.backgroundColor = UIColor.red.cgColor改成myView.backgroundColor = UIColor.red
@k8mil，对不起，我都试过了。就在我复制粘贴代码sn-p的时候，我用了layer.backgroundColor。我编辑了我的帖子
您是否尝试在背景颜色的红色上设置不透明度 0.5 以查看白色是否透出？
你试过maskToBounds或clipToBounds值到true
@rjndra，是的，我都试过了

标签： ios swift uiview calayer

【解决方案1】：

您可以像下面这样使用自定义边框和背景

@IBDesignable class view_border_background: UIView {

private let gradientLayer : CAGradientLayer = CAGradientLayer()

 //let gradientLayer = CAGradientLayer()

// IBInspectable properties for the gradient colors
@IBInspectable var bottomColor: UIColor = UIColor(hex: 0xe5e5e5)
@IBInspectable var middleColor: UIColor = UIColor(hex: 0xe5e5e5)
@IBInspectable var topColor: UIColor = UIColor(hex: 0xe5e5e5)
@IBInspectable var bottomColorAlpha: CGFloat = 1.0
@IBInspectable var middleColorAlpha: CGFloat = 1.0
@IBInspectable var topColorAlpha: CGFloat = 1.0

// IBInspectable properties for rounded corners and border color / width
@IBInspectable var cornerSize: CGFloat = 0
@IBInspectable var borderSize: CGFloat = 1
@IBInspectable var borderColor: UIColor = colorize(hex: 0x8bc218)
@IBInspectable var borderAlpha: CGFloat = 1.0

override func draw(_ rect: CGRect) {


    // set up border and cornerRadius
    self.layer.cornerRadius = cornerSize
    self.layer.borderColor = borderColor.withAlphaComponent(borderAlpha).cgColor
    self.layer.borderWidth = borderSize

    self.layer.masksToBounds = true

    // set up gradient

    gradientLayer.frame = rect
    let c1 = bottomColor.withAlphaComponent(bottomColorAlpha).cgColor
    let c2 = middleColor.withAlphaComponent(middleColorAlpha).cgColor
    let c3 = topColor.withAlphaComponent(topColorAlpha).cgColor
    gradientLayer.colors = [c3, c2, c1]
    gradientLayer.startPoint = CGPoint(x: 0, y: 0)
    gradientLayer.endPoint = CGPoint(x: 0, y: 0)
   self.layer.insertSublayer(gradientLayer, at: 0)


}
override public func layoutSubviews() {
    super.layoutSubviews()

    gradientLayer.frame = self.layer.bounds
    }

  }

十六进制颜色转换

func colorize (hex: Int, alpha: Double = 1) -> UIColor {
let red = Double((hex & 0xFF0000) >> 16) / 255.0
let green = Double((hex & 0xFF00) >> 8) / 255.0
let blue = Double((hex & 0xFF)) / 255.0
var color: UIColor = UIColor( red: CGFloat(red), green: CGFloat(green), blue: CGFloat(blue), alpha:CGFloat(alpha) )
return color

}

只需在 VIView 中添加“view_border_background”显示身份检查器

【讨论】：

【解决方案2】：

我已经测试过了，在我的模拟器中运行良好

override func viewDidLoad() {
    super.viewDidLoad()

    myView.layer.cornerRadius = myView.frame.size.width/2 //first make your view as rounded. 

    myView.layer.backgroundColor = UIColor.red.cgColor //convert into cgColor
    myView.layer.borderColor = UIColor.white.cgColor
    myView.layer.borderWidth = 3
}

【讨论】：

我都试过了：UIView.backgroundColor 和 UIView.layer.backgroundColor。这没有帮助。