swift - 如何在 Swift 中将 Color Literal 转换为 cgColor？

Question

var CodeBackground = #colorLiteral(red: 0.1294117647, green: 0.1294117647, blue: 0.1960784314, alpha: 1)

cells?.layer.borderColor = //... how can i set this color literal to cgColor?

据我所知，如何在 Swift 中将该 UIColor 转换为 cgColor

例如

UIColor.black.cgColor

宾果游戏，但是 Swift 中的颜色文字到 cgColor 呢？

谢谢你。

标签： swiftuitableviewuicolorcgcolor

Answer 1

• 作为，您已经知道使用colorLiteralas的更简单方法cgcolor，我将跳到另一种方法......

• 为此，您需要一个自定义函数，它从 中获取颜色值（红色、绿色、蓝色）colorLiteral，如下所示

  extension UIColor {
      func rgb() -> (red:Int, green:Int, blue:Int, alpha:Int)? {
      var fRed : CGFloat = 0
      var fGreen : CGFloat = 0
      var fBlue : CGFloat = 0
      var fAlpha: CGFloat = 0
      if self.getRed(&fRed, green: &fGreen, blue: &fBlue, alpha: &fAlpha) {
          let iRed = Int(fRed * 255.0)
          let iGreen = Int(fGreen * 255.0)
          let iBlue = Int(fBlue * 255.0)
          let iAlpha = Int(fAlpha)
  
          _ = (iAlpha << 24) + (iRed << 16) + (iGreen << 8) + iBlue
          return (red:iRed, green:iGreen, blue:iBlue, alpha:iAlpha)
      } else {
          // Could not extract RGBA components:
          return nil
      }
  }
  }
  //It's more convenient to use function in `UIColor` extension
  

• 现在，创建此函数后，您可以转换colorliteral为cgColor如下...

  let CodeBackground = #colorLiteral(red: 0.1294117647, green: 0.1294117647, blue: 0.1960784314, alpha: 1)
  let rgblit = CodeBackground.rgb()
  let Converted_cgColor = CGColor(srgbRed: CGFloat(integerLiteral: rgblit!.red), green: CGFloat(integerLiteral: rgblit!.green), blue: CGFloat(integerLiteral: rgblit!.blue), alpha: CGFloat(integerLiteral: rgblit!.alpha))
  

• 可以直接使用Converted_cgColorlike

  cells?.layer.borderColor = Converted_cgColor
  

希望能帮助到你