如何使用十六进制颜色值

问题描述 投票：291回答：33

我试图在Swift中使用十六进制颜色值，而不是UIColor允许你使用的几个标准颜色值，但我不知道如何做到这一点。

示例：我如何使用#ffffff作为颜色？

ios swift uicolor
33个回答
610
投票

qazxsw poi实际上是十六进制表示法中的3种颜色成分 - 红色qazxsw poi，绿色qazxsw poi和蓝色#ffffff。您可以使用ff前缀在Swift中编写十六进制表示法，例如ff

为了简化转换，让我们创建一个取整数（0 - 255）值的初始值设定项：

ff

用法：

0x

如何获得阿尔法？

根据您的使用情况，您可以简单地使用原生的0xFF方法，例如

extension UIColor {
   convenience init(red: Int, green: Int, blue: Int) {
       assert(red >= 0 && red <= 255, "Invalid red component")
       assert(green >= 0 && green <= 255, "Invalid green component")
       assert(blue >= 0 && blue <= 255, "Invalid blue component")

       self.init(red: CGFloat(red) / 255.0, green: CGFloat(green) / 255.0, blue: CGFloat(blue) / 255.0, alpha: 1.0)
   }

   convenience init(rgb: Int) {
       self.init(
           red: (rgb >> 16) & 0xFF,
           green: (rgb >> 8) & 0xFF,
           blue: rgb & 0xFF
       )
   }
}

或者您可以在上述方法中添加其他（可选）参数：

let color = UIColor(red: 0xFF, green: 0xFF, blue: 0xFF)
let color2 = UIColor(rgb: 0xFFFFFF)

（我们无法将参数命名为UIColor.withAlphaComponent，因为名称与现有的初始化程序发生冲突）。

被称为：

let semitransparentBlack = UIColor(rgb: 0x000000).withAlphaComponent(0.5)

要将alpha作为0-255的整数，我们可以

convenience init(red: Int, green: Int, blue: Int, a: CGFloat = 1.0) {
    self.init(
        red: CGFloat(red) / 255.0,
        green: CGFloat(green) / 255.0,
        blue: CGFloat(blue) / 255.0,
        alpha: a
    )
}

convenience init(rgb: Int, a: CGFloat = 1.0) {
    self.init(
        red: (rgb >> 16) & 0xFF,
        green: (rgb >> 8) & 0xFF,
        blue: rgb & 0xFF,
        a: a
    )
}

被称为

alpha

或者以前方法的组合。绝对不需要使用字符串。

10
投票

以编程方式添加颜色的最简单方法是使用ColorLiteral。

只需添加属性ColorLiteral，如示例所示，Xcode将提示您可以选择的整个颜色列表。这样做的好处是代码较少，添加HEX值或RGB。您还将从故事板中获取最近使用的颜色。

示例：self.view.backgroundColor = ColorLiteral UIColor(hex: 0xffffff) // r 1.0 g 1.0 b 1.0 a 1.0 UIColor(hex: 0xffffff, alpha: 0.5) // r 1.0 g 1.0 b 1.0 a 0.5

6
投票

另一种方法

Swift 3.0

为UIColor写一个扩展名

This

你可以直接用这样的十六进制创建UIColor

let rgbValue = 0xFFEEDD
let r = Float((rgbValue & 0xFF0000) >> 16)/255.0
let g = Float((rgbValue & 0xFF00) >> 8)/255.0
let b = Float((rgbValue & 0xFF))/255.0
self.backgroundColor = UIColor(red:r, green: g, blue: b, alpha: 1.0)
5
投票

最新的swift3版本

enter image description here

在你的班级中使用或在任何地方转换成十六进制颜色就像这样使用uicolor

// To change the HexaDecimal value to Corresponding Color
extension UIColor
{
    class func uicolorFromHex(_ rgbValue:UInt32, alpha : CGFloat)->UIColor

    {
        let red = CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0
        let green = CGFloat((rgbValue & 0xFF00) >> 8) / 255.0
        let blue = CGFloat(rgbValue & 0xFF) / 255.0
        return UIColor(red:red, green:green, blue:blue, alpha: alpha)
    }
}
4
投票

这是let carrot = UIColor.uicolorFromHex(0xe67e22, alpha: 1)) 上的Swift扩展，它带有十六进制字符串：

        extension UIColor {
convenience init(hexString: String) {
    let hex = hexString.trimmingCharacters(in: CharacterSet.alphanumerics.inverted)
    var int = UInt32()
    Scanner(string: hex).scanHexInt32(&int)
    let a, r, g, b: UInt32
    switch hex.characters.count {
    case 3: // RGB (12-bit)
        (a, r, g, b) = (255, (int >> 8) * 17, (int >> 4 & 0xF) * 17, (int & 0xF) * 17)
    case 6: // RGB (24-bit)
        (a, r, g, b) = (255, int >> 16, int >> 8 & 0xFF, int & 0xFF)
    case 8: // ARGB (32-bit)
        (a, r, g, b) = (int >> 24, int >> 16 & 0xFF, int >> 8 & 0xFF, int & 0xFF)
    default:
        (a, r, g, b) = (255, 0, 0, 0)
    }
      self.init(red: CGFloat(r) / 255, green: CGFloat(g) / 255, blue:      CGFloat(b) / 255, alpha: CGFloat(a) / 255)
}
}
4
投票

十六进制验证

基于 let color1 = UIColor(hexString: "#FF323232") 回答

细节

  • Xcode 10.0，Swift 4.2
  • Xcode 10.2.1（10E1001），Swift 5

解

UIColor

用法

import UIKit

extension UIColor {

    convenience init(hexString: String) {
        // Trim leading '#' if needed
        var cleanedHexString = hexString
        if hexString.hasPrefix("#") {
//            cleanedHexString = dropFirst(hexString) // Swift 1.2
            cleanedHexString = String(hexString.characters.dropFirst()) // Swift 2
        }

        // String -> UInt32
        var rgbValue: UInt32 = 0
        NSScanner(string: cleanedHexString).scanHexInt(&rgbValue)

        // UInt32 -> R,G,B
        let red = CGFloat((rgbValue >> 16) & 0xff) / 255.0
        let green = CGFloat((rgbValue >> 08) & 0xff) / 255.0
        let blue = CGFloat((rgbValue >> 00) & 0xff) / 255.0

        self.init(red: red, green: green, blue: blue, alpha: 1.0)
    }

}
3
投票
Eduardo

如何使用

import UIKit

extension UIColor {

    convenience init(r: UInt8, g: UInt8, b: UInt8, alpha: CGFloat = 1.0) {
        let divider: CGFloat = 255.0
        self.init(red: CGFloat(r)/divider, green: CGFloat(g)/divider, blue: CGFloat(b)/divider, alpha: alpha)
    }

    private convenience init(rgbWithoutValidation value: Int32, alpha: CGFloat = 1.0) {
        self.init(
            r: UInt8((value & 0xFF0000) >> 16),
            g: UInt8((value & 0x00FF00) >> 8),
            b: UInt8(value & 0x0000FF),
            alpha: alpha
        )
    }

    convenience init?(rgb: Int32, alpha: CGFloat = 1.0) {
        if rgb > 0xFFFFFF || rgb < 0 { return nil }
        self.init(rgbWithoutValidation: rgb, alpha: alpha)
    }

    convenience init?(hex: String, alpha: CGFloat = 1.0) {
        var charSet = CharacterSet.whitespacesAndNewlines
        charSet.insert("#")
        let _hex = hex.trimmingCharacters(in: charSet)
        guard _hex.range(of: "^[0-9A-Fa-f]{6}$", options: .regularExpression) != nil else { return nil }
        var rgb: UInt32 = 0
        Scanner(string: _hex).scanHexInt32(&rgb)
        self.init(rgbWithoutValidation: Int32(rgb), alpha: alpha)
    }
}
3
投票

我已经从这个答案线程中合并了一些想法并将其更新为Swift 4。

let alpha: CGFloat = 1.0

// Hex
print(UIColor(rgb: 0x4F9BF5) ?? "nil")
print(UIColor(rgb: 0x4F9BF5, alpha: alpha) ?? "nil")
print(UIColor(rgb: 5217269) ?? "nil")
print(UIColor(rgb: -5217269) ?? "nil")                  // = nil
print(UIColor(rgb: 0xFFFFFF1) ?? "nil")                 // = nil

// String
print(UIColor(hex: "4F9BF5") ?? "nil")
print(UIColor(hex: "4F9BF5", alpha: alpha) ?? "nil")
print(UIColor(hex: "#4F9BF5") ?? "nil")
print(UIColor(hex: "#4F9BF5", alpha: alpha) ?? "nil")
print(UIColor(hex: "#4F9BF56") ?? "nil")                // = nil
print(UIColor(hex: "#blabla") ?? "nil")                 // = nil

// RGB
print(UIColor(r: 79, g: 155, b: 245))
print(UIColor(r: 79, g: 155, b: 245, alpha: alpha))
//print(UIColor(r: 792, g: 155, b: 245, alpha: alpha))  // Compiler will throw an error, r,g,b = [0...255]

然后你可以像这样使用它：

public static func hexStringToUIColor (hex:String) -> UIColor {
    var cString:String = hex.trimmingCharacters(in: .whitespacesAndNewlines).uppercased()

    if (cString.hasPrefix("#")) {
        cString.remove(at: cString.startIndex)
    }

    if ((cString.characters.count) == 6) {

        var rgbValue:UInt32 = 0
        Scanner(string: cString).scanHexInt32(&rgbValue)

        return UIColor(
            red: CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0,
            green: CGFloat((rgbValue & 0x00FF00) >> 8) / 255.0,
            blue: CGFloat(rgbValue & 0x0000FF) / 255.0,
            alpha: CGFloat(1.0)
        )
    }else if ((cString.characters.count) == 8) {

        var rgbValue:UInt32 = 0
        Scanner(string: cString).scanHexInt32(&rgbValue)

        return UIColor(
            red: CGFloat((rgbValue & 0x00FF0000) >> 16) / 255.0,
            green: CGFloat((rgbValue & 0x0000FF00) >> 8) / 255.0,
            blue: CGFloat(rgbValue & 0x000000FF) / 255.0,
            alpha: CGFloat((rgbValue & 0xFF000000) >> 24) / 255.0
        )
    }else{
        return UIColor.gray
    }
}
0
投票

支持7种十六进制颜色类型

有7种十六进制颜色格式：“”＃FF0000“，”0xFF0000“，”FF0000“，”F00“，”红色“，0x00FF00,16711935

var color: UIColor = hexStringToUIColor(hex: "#00ff00"); // Without transparency
var colorWithTransparency: UIColor = hexStringToUIColor(hex: "#dd00ff00"); // With transparency

注意：这不是“单文件解决方案”，存在一些依赖关系，但是搜索它们可能比从头开始研究这个更快。

extension UIColor { convenience init(hex: String, alpha: CGFloat = 1.0) { var cString:String = hex.trimmingCharacters(in: .whitespacesAndNewlines).uppercased() if (cString.hasPrefix("#")) { cString.removeFirst() } if ((cString.count) != 6) { self.init(hex: "ff0000") // return red color for wrong hex input return } var rgbValue: UInt32 = 0 Scanner(string: cString).scanHexInt32(&rgbValue) self.init(red: CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0, green: CGFloat((rgbValue & 0x00FF00) >> 8) / 255.0, blue: CGFloat(rgbValue & 0x0000FF) / 255.0, alpha: alpha) } }

固定链接： UIColor(hex: "#ff0000") // with # UIColor(hex: "ff0000") // without # UIColor(hex: "ff0000", alpha: 0.5) // using optional alpha value

0
投票

Swift 2.0

下面的代码在xcode 7.2上测试

NSColorParser.nsColor("#FF0000",1)//red nsColor
NSColorParser.nsColor("FF0",1)//red nsColor
NSColorParser.nsColor("0xFF0000",1)//red nsColor
NSColorParser.nsColor("#FF0000",1)//red nsColor
NSColorParser.nsColor("FF0000",1)//red nsColor
NSColorParser.nsColor(0xFF0000,1)//red nsColor
NSColorParser.nsColor(16711935,1)//red nsColor
0
投票

Swift 2.0：

扩展UIColor。

https://github.com/eonist/swift-utils/blob/2882002682c4d2a3dc7cb3045c45f66ed59d566d/geom/color/NSColorParser.swift

用法：

https://github.com/eonist/Element/wiki/Progress#supporting-7-hex-color-types
300
投票

这是一个采用十六进制字符串并返回UIColor的函数。 （您可以使用以下任一格式输入十六进制字符串：let color = UIColor(red: 0xFF, green: 0xFF, blue: 0xFF, a: 0.5) let color2 = UIColor(rgb: 0xFFFFFF, a: 0.5) 或convenience init(red: Int, green: Int, blue: Int, a: Int = 0xFF) { self.init( red: CGFloat(red) / 255.0, green: CGFloat(green) / 255.0, blue: CGFloat(blue) / 255.0, alpha: CGFloat(a) / 255.0 ) } // let's suppose alpha is the first component (ARGB) convenience init(argb: Int) { self.init( red: (argb >> 16) & 0xFF, green: (argb >> 8) & 0xFF, blue: argb & 0xFF, a: (argb >> 24) & 0xFF ) } ）

用法：

let color = UIColor(red: 0xFF, green: 0xFF, blue: 0xFF, a: 0xFF)
let color2 = UIColor(argb: 0xFFFFFFFF)

斯威夫特5 :(斯威夫特4+）

#ffffff

斯威夫特3：

ffffff

斯威夫特2：

var color1 = hexStringToUIColor("#d3d3d3")

资料来源：func hexStringToUIColor (hex:String) -> UIColor { var cString:String = hex.trimmingCharacters(in: .whitespacesAndNewlines).uppercased() if (cString.hasPrefix("#")) { cString.remove(at: cString.startIndex) } if ((cString.count) != 6) { return UIColor.gray } var rgbValue:UInt32 = 0 Scanner(string: cString).scanHexInt32(&rgbValue) return UIColor( red: CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0, green: CGFloat((rgbValue & 0x00FF00) >> 8) / 255.0, blue: CGFloat(rgbValue & 0x0000FF) / 255.0, alpha: CGFloat(1.0) ) }

编辑：更新了代码。谢谢，Hlung，jaytrixz和Ahmad F！

0
投票

Swift 2.0：

在viewDidLoad（）中

import UIKit
extension UIColor{

    public convenience init?(colorCodeInHex: String, alpha: Float = 1.0){

        var filterColorCode:String =  colorCodeInHex.stringByReplacingOccurrencesOfString("#", withString: "")

        if  filterColorCode.characters.count != 6 {
            self.init(red: 0.0, green: 0.0, blue: 0.0, alpha: CGFloat(alpha))
            return
        }

        filterColorCode = filterColorCode.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet()).uppercaseString

        var range = Range(start: filterColorCode.startIndex.advancedBy(0), end: filterColorCode.startIndex.advancedBy(2))
        let rString = filterColorCode.substringWithRange(range)

        range = Range(start: filterColorCode.startIndex.advancedBy(2), end: filterColorCode.startIndex.advancedBy(4))
        let gString = filterColorCode.substringWithRange(range)


        range = Range(start: filterColorCode.startIndex.advancedBy(4), end: filterColorCode.startIndex.advancedBy(6))
        let bString = filterColorCode.substringWithRange(range)

        var r:CUnsignedInt = 0, g:CUnsignedInt = 0, b:CUnsignedInt = 0;
        NSScanner(string: rString).scanHexInt(&r)
        NSScanner(string: gString).scanHexInt(&g)
        NSScanner(string: bString).scanHexInt(&b)


        self.init(red: CGFloat(r) / 255.0, green: CGFloat(g) / 255.0, blue: CGFloat(b) / 255.0, alpha: CGFloat(alpha))
        return
    }
}
0
投票

对于swift 3

extension UIColor {
    convenience init(hexString:String) {
        let hexString:NSString = hexString.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet())
        let scanner            = NSScanner(string: hexString as String)
        if (hexString.hasPrefix("#")) {
            scanner.scanLocation = 1
        }

        var color:UInt32 = 0
        scanner.scanHexInt(&color)

        let mask = 0x000000FF
        let r = Int(color >> 16) & mask
        let g = Int(color >> 8) & mask
        let b = Int(color) & mask

        let red   = CGFloat(r) / 255.0
        let green = CGFloat(g) / 255.0
        let blue  = CGFloat(b) / 255.0
        self.init(red:red, green:green, blue:blue, alpha:1)
    }

    func toHexString() -> String {
        var r:CGFloat = 0
        var g:CGFloat = 0
        var b:CGFloat = 0
        var a:CGFloat = 0
        getRed(&r, green: &g, blue: &b, alpha: &a)
        let rgb:Int = (Int)(r*255)<<16 | (Int)(g*255)<<8 | (Int)(b*255)<<0
        return NSString(format:"#%06x", rgb) as String
    }

}
0
投票

您可以在UIColor上使用此扩展，它将您的字符串（十六进制，RGBA）转换为UIColor，反之亦然。

//Hex to Color
    let countPartColor =  UIColor(hexString: "E43038")

//Color to Hex
let colorHexString =  UIColor(red: 228, green: 48, blue: 56, alpha: 1.0).toHexString()
0
投票

UIColor扩展，这将极大地帮助您！ （版本：Swift 4.0）

 var viewColor:UIColor
    viewColor = UIColor()
    let colorInt:UInt
    colorInt = 0x000000
    viewColor = UIColorFromRGB(colorInt)
    self.View.backgroundColor=viewColor



func UIColorFromRGB(rgbValue: UInt) -> UIColor {
    return UIColor(
        red: CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0,
        green: CGFloat((rgbValue & 0x00FF00) >> 8) / 255.0,
        blue: CGFloat(rgbValue & 0x0000FF) / 255.0,
        alpha: CGFloat(1.0)
    )
}
0
投票

RGBA Version Swift 3/4

我喜欢@Luca的答案，因为我认为它是最优雅的。

但是我不希望在ARGB中指定我的颜色。我更喜欢RGBA +，我还需要处理为每个通道“#FFFA”指定1个字符的字符串。

如果它包含在字符串中，这个版本还会添加错误抛出+剥离'＃'字符。这是我为Swift修改的表单。

extension String {
    var hexColor: UIColor {        
        let hex = trimmingCharacters(in: CharacterSet.alphanumerics.inverted)
        var int = UInt32()       
        Scanner(string: hex).scanHexInt32(&int)
        let a, r, g, b: UInt32
        switch hex.characters.count {
        case 3: // RGB (12-bit)
            (a, r, g, b) = (255, (int >> 8) * 17, (int >> 4 & 0xF) * 17, (int & 0xF) * 17)
        case 6: // RGB (24-bit)
            (a, r, g, b) = (255, int >> 16, int >> 8 & 0xFF, int & 0xFF)
        case 8: // ARGB (32-bit)
            (a, r, g, b) = (int >> 24, int >> 16 & 0xFF, int >> 8 & 0xFF, int & 0xFF)
        default:
            return .clear
        }
        return UIColor(red: CGFloat(r) / 255, green: CGFloat(g) / 255, blue: CGFloat(b) / 255, alpha: CGFloat(a) / 255)
    }
}
0
投票

你可以在swift 5中使用它

SWIFT 5

extension UIColor {

  //Convert RGBA String to UIColor object
  //"rgbaString" must be separated by space "0.5 0.6 0.7 1.0" 50% of Red 60% of Green 70% of Blue Alpha 100%
  public convenience init?(rgbaString : String){
      self.init(ciColor: CIColor(string: rgbaString))
  }

  //Convert UIColor to RGBA String
  func toRGBAString()-> String {
    var r: CGFloat = 0
    var g: CGFloat = 0
    var b: CGFloat = 0
    var a: CGFloat = 0
    self.getRed(&r, green: &g, blue: &b, alpha: &a)
    return "\(r) \(g) \(b) \(a)"
  }

  //return UIColor from Hexadecimal Color string
  public convenience init?(hexString: String) {  
    let r, g, b, a: CGFloat

    if hexString.hasPrefix("#") {
      let start = hexString.index(hexString.startIndex, offsetBy: 1)
      let hexColor = hexString.substring(from: start)

      if hexColor.characters.count == 8 {
        let scanner = Scanner(string: hexColor)
        var hexNumber: UInt64 = 0

        if scanner.scanHexInt64(&hexNumber) {
          r = CGFloat((hexNumber & 0xff000000) >> 24) / 255
          g = CGFloat((hexNumber & 0x00ff0000) >> 16) / 255
          b = CGFloat((hexNumber & 0x0000ff00) >> 8) / 255
          a = CGFloat(hexNumber & 0x000000ff) / 255
          self.init(red: r, green: g, blue: b, alpha: a)
          return
        }
      }
    }

    return nil
  }

  // Convert UIColor to Hexadecimal String
  func toHexString() -> String {
    var r: CGFloat = 0
    var g: CGFloat = 0
    var b: CGFloat = 0
    var a: CGFloat = 0
    self.getRed(&r, green: &g, blue: &b, alpha: &a)
    return String(
        format: "%02X%02X%02X",
        Int(r * 0xff),
        Int(g * 0xff),
        Int(b * 0xff))
  }
}
-1
投票

只是第一个答案的一些补充

（没有检查过alpha，可能需要添加一个qazxsw poi）：

import UIKit
extension UIColor {
/// rgb颜色
convenience init(r: CGFloat, g: CGFloat, b: CGFloat) {
    self.init(red: r/255.0 ,green: g/255.0 ,blue: b/255.0 ,alpha:1.0)
}

/// 纯色（用于灰色）
convenience init(gray: CGFloat) {
    self.init(red: gray/255.0 ,green: gray/255.0 ,blue: gray/255.0 ,alpha:1.0)
}
/// 随机色
class func randomCGColor() -> UIColor {
    return UIColor(r: CGFloat(arc4random_uniform(256)), g: CGFloat(arc4random_uniform(256)), b: CGFloat(arc4random_uniform(256)))
}

/// hex颜色-Int
convenience init(hex:Int, alpha:CGFloat = 1.0) {
    self.init(
        red:   CGFloat((hex & 0xFF0000) >> 16) / 255.0,
        green: CGFloat((hex & 0x00FF00) >> 8)  / 255.0,
        blue:  CGFloat((hex & 0x0000FF) >> 0)  / 255.0,
        alpha: alpha
    )
}
/// hex颜色-String
convenience init(hexString: String){
    var red:   CGFloat = 0.0
    var green: CGFloat = 0.0
    var blue:  CGFloat = 0.0
    var alpha: CGFloat = 1.0
    let scanner = Scanner(string: hexString)
    var hexValue: CUnsignedLongLong = 0
    if scanner.scanHexInt64(&hexValue) {
        switch (hexString.characters.count) {
        case 3:
            red   = CGFloat((hexValue & 0xF00) >> 8)       / 15.0
            green = CGFloat((hexValue & 0x0F0) >> 4)       / 15.0
            blue  = CGFloat(hexValue & 0x00F)              / 15.0
        case 4:
            red   = CGFloat((hexValue & 0xF000) >> 12)     / 15.0
            green = CGFloat((hexValue & 0x0F00) >> 8)      / 15.0
            blue  = CGFloat((hexValue & 0x00F0) >> 4)      / 15.0
            alpha = CGFloat(hexValue & 0x000F)             / 15.0
        case 6:
            red   = CGFloat((hexValue & 0xFF0000) >> 16)   / 255.0
            green = CGFloat((hexValue & 0x00FF00) >> 8)    / 255.0
            blue  = CGFloat(hexValue & 0x0000FF)           / 255.0
        case 8:
            alpha = CGFloat((hexValue & 0xFF000000) >> 24) / 255.0
            red   = CGFloat((hexValue & 0x00FF0000) >> 16) / 255.0
            green = CGFloat((hexValue & 0x0000FF00) >> 8)  / 255.0
            blue  = CGFloat(hexValue & 0x000000FF)         / 255.0
        default:
            log.info("Invalid RGB string, number of characters after '#' should be either 3, 4, 6 or 8")
        }
    } else {
        log.error("Scan hex error")
    }
    self.init(red:red, green:green, blue:blue, alpha:alpha)
}}
-1
投票

Swift 2.3：UIColor扩展。我觉得它更简单。

public enum ColourParsingError: Error
{

    case invalidInput(String)
}
extension UIColor {
    public convenience init(hexString: String) throws
    {
        let hexString = hexString.replacingOccurrences(of: "#", with: "")
        let hex = hexString.trimmingCharacters(in:NSCharacterSet.alphanumerics.inverted)
        var int = UInt32()
        Scanner(string: hex).scanHexInt32(&int)
        let a, r, g, b: UInt32
        switch hex.count 
        {
        case 3: // RGB (12-bit)
            (r, g, b,a) = ((int >> 8) * 17, (int >> 4 & 0xF) * 17, (int & 0xF) * 17,255)
        //iCSS specification in the form of #F0FA
        case 4: // RGB (24-bit)
            (r, g, b,a) = ((int >> 12) * 17, (int >> 8 & 0xF) * 17, (int >> 4 & 0xF) * 17, (int & 0xF) * 17)
        case 6: // RGB (24-bit)
            (r, g, b, a) = (int >> 16, int >> 8 & 0xFF, int & 0xFF,255)
        case 8: // ARGB (32-bit)
            (r, g, b, a) = (int >> 24, int >> 16 & 0xFF, int >> 8 & 0xFF, int & 0xFF)
        default:
            throw ColourParsingError.invalidInput("String is not a valid hex colour string: \(hexString)")
        }
        self.init(red: CGFloat(r) / 255, green: CGFloat(g) / 255, blue: CGFloat(b) / 255, alpha: CGFloat(a) / 255)
    }
}

用法：

import UIKit

extension UIColor {
    static func hexStringToUIColor (hex:String) -> UIColor {
        var cString:String = hex.trimmingCharacters(in: .whitespacesAndNewlines).uppercased()

        if (cString.hasPrefix("#")) {
            cString.remove(at: cString.startIndex)
        }

        if ((cString.count) != 6) {
            return UIColor.gray
        }

        var rgbValue:UInt32 = 0
        Scanner(string: cString).scanHexInt32(&rgbValue)

        return UIColor(
            red: CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0,
            green: CGFloat((rgbValue & 0x00FF00) >> 8) / 255.0,
            blue: CGFloat(rgbValue & 0x0000FF) / 255.0,
            alpha: CGFloat(1.0)
        )
    }
}
-1
投票

斯威夫特3

if netHext > 0xffffff

使用：

extension UIColor {

struct COLORS_HEX {
    static let Primary = 0xffffff
    static let PrimaryDark = 0x000000
    static let Accent = 0xe89549
    static let AccentDark = 0xe27b2a
    static let TextWhiteSemiTransparent = 0x80ffffff
}

convenience init(red: Int, green: Int, blue: Int, alphaH: Int) {
    assert(red >= 0 && red <= 255, "Invalid red component")
    assert(green >= 0 && green <= 255, "Invalid green component")
    assert(blue >= 0 && blue <= 255, "Invalid blue component")
    assert(alphaH >= 0 && alphaH <= 255, "Invalid alpha component")

    self.init(red: CGFloat(red) / 255.0, green: CGFloat(green) / 255.0, blue: CGFloat(blue) / 255.0, alpha: CGFloat(alphaH) / 255.0)
}

convenience init(netHex:Int) {
    self.init(red:(netHex >> 16) & 0xff, green:(netHex >> 8) & 0xff, blue:netHex & 0xff, alphaH: (netHex >> 24) & 0xff)
}

}
-1
投票

Swift 4.0

使用此单行方法

extension UIColor {
    static func colorFromHex(hexString: String, alpha: CGFloat = 1) -> UIColor {
        //checking if hex has 7 characters or not including '#'
        if hexString.characters.count < 7 {
            return UIColor.whiteColor()
        }
        //string by removing hash
        let hexStringWithoutHash = hexString.substringFromIndex(hexString.startIndex.advancedBy(1))

        //I am extracting three parts of hex color Red (first 2 characters), Green (middle 2 characters), Blue (last two characters)
        let eachColor = [
            hexStringWithoutHash.substringWithRange(hexStringWithoutHash.startIndex...hexStringWithoutHash.startIndex.advancedBy(1)),
            hexStringWithoutHash.substringWithRange(hexStringWithoutHash.startIndex.advancedBy(2)...hexStringWithoutHash.startIndex.advancedBy(3)),
            hexStringWithoutHash.substringWithRange(hexStringWithoutHash.startIndex.advancedBy(4)...hexStringWithoutHash.startIndex.advancedBy(5))]

        let hexForEach = eachColor.map {CGFloat(Int($0, radix: 16) ?? 0)} //radix is base of numeric system you want to convert to, Hexadecimal has base 16

        //return the color by making color
        return UIColor(red: hexForEach[0] / 255, green: hexForEach[1] / 255, blue: hexForEach[2] / 255, alpha: alpha)
    }
}

您必须创建新类或使用任何需要使用Hex颜色的控制器。此扩展类为您提供将Hex转换为RGB颜色的UIColor。

let color = UIColor.colorFromHex("#25ac09")
145
投票

Swift 4 UIColor扩展：

func hexStringToUIColor (hex:String) -> UIColor {
    var cString:String = hex.trimmingCharacters(in: .whitespacesAndNewlines).uppercased()

    if (cString.hasPrefix("#")) {
        cString.remove(at: cString.startIndex)
    }

    if ((cString.characters.count) != 6) {
        return UIColor.gray
    }

    var rgbValue:UInt32 = 0
    Scanner(string: cString).scanHexInt32(&rgbValue)

    return UIColor(
        red: CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0,
        green: CGFloat((rgbValue & 0x00FF00) >> 8) / 255.0,
        blue: CGFloat(rgbValue & 0x0000FF) / 255.0,
        alpha: CGFloat(1.0)
    )
}

用法：

func hexStringToUIColor (hex:String) -> UIColor {
    var cString:String = hex.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet() as NSCharacterSet).uppercaseString

    if (cString.hasPrefix("#")) {
      cString = cString.substringFromIndex(cString.startIndex.advancedBy(1))
    }

    if ((cString.characters.count) != 6) {
      return UIColor.grayColor()
    }

    var rgbValue:UInt32 = 0
    NSScanner(string: cString).scanHexInt(&rgbValue)

    return UIColor(
        red: CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0,
        green: CGFloat((rgbValue & 0x00FF00) >> 8) / 255.0,
        blue: CGFloat(rgbValue & 0x0000FF) / 255.0,
        alpha: CGFloat(1.0)
    )
}

Swift 2.x版本：

arshad/gist:de147c42d7b3063ef7bc
-2
投票
extension UIColor {
    convenience init(r: Int, g: Int, b: Int, a: Int = 255) {
        self.init(red: CGFloat(r) / 255.0, green: CGFloat(g) / 255.0, blue: CGFloat(b) / 255.0, alpha: CGFloat(a) / 255.0)
    }

    convenience init(netHex:Int) {
        self.init(r:(netHex >> 16) & 0xff, g:(netHex >> 8) & 0xff, b:netHex & 0xff)
    }
}

使用此扩展名如：

self.view.backgroundColor = UIColor(netHex: 0x27ae60)
67
投票

extension UIColor { convenience init(hexString: String) { let hex = hexString.trimmingCharacters(in: CharacterSet.alphanumerics.inverted) var int = UInt32() Scanner(string: hex).scanHexInt32(&int) let a, r, g, b: UInt32 switch hex.count { case 3: // RGB (12-bit) (a, r, g, b) = (255, (int >> 8) * 17, (int >> 4 & 0xF) * 17, (int & 0xF) * 17) case 6: // RGB (24-bit) (a, r, g, b) = (255, int >> 16, int >> 8 & 0xFF, int & 0xFF) case 8: // ARGB (32-bit) (a, r, g, b) = (int >> 24, int >> 16 & 0xFF, int >> 8 & 0xFF, int & 0xFF) default: (a, r, g, b) = (255, 0, 0, 0) } self.init(red: CGFloat(r) / 255, green: CGFloat(g) / 255, blue: CGFloat(b) / 255, alpha: CGFloat(a) / 255) } } ：

let darkGrey = UIColor(hexString: "#757575")

extension UIColor { convenience init(hexString: String) { let hex = hexString.stringByTrimmingCharactersInSet(NSCharacterSet.alphanumericCharacterSet().invertedSet) var int = UInt32() NSScanner(string: hex).scanHexInt(&int) let a, r, g, b: UInt32 switch hex.characters.count { case 3: // RGB (12-bit) (a, r, g, b) = (255, (int >> 8) * 17, (int >> 4 & 0xF) * 17, (int & 0xF) * 17) case 6: // RGB (24-bit) (a, r, g, b) = (255, int >> 16, int >> 8 & 0xFF, int & 0xFF) case 8: // ARGB (32-bit) (a, r, g, b) = (int >> 24, int >> 16 & 0xFF, int >> 8 & 0xFF, int & 0xFF) default: (a, r, g, b) = (255, 0, 0, 0) } self.init(red: CGFloat(r) / 255, green: CGFloat(g) / 255, blue: CGFloat(b) / 255, alpha: CGFloat(a) / 255) } } ：

UIColor

用法

extension UIColor {

    convenience init(hex: Int) {
        let components = (
            R: CGFloat((hex >> 16) & 0xff) / 255,
            G: CGFloat((hex >> 08) & 0xff) / 255,
            B: CGFloat((hex >> 00) & 0xff) / 255
        )
        self.init(red: components.R, green: components.G, blue: components.B, alpha: 1)
    }

}
35
投票

斯威夫特4：结合Sulthan和Luca Torella的答案：

CGColor

用法示例：

extension CGColor {

    class func colorWithHex(hex: Int) -> CGColorRef {

        return UIColor(hex: hex).CGColor

    }

}
24
投票

使用Swift 2.0和Xcode 7.0.1，您可以创建此功能：

let purple = UIColor(hex: 0xAB47BC)

然后以这种方式使用它：

extension UIColor {
    convenience init(hexFromString:String, alpha:CGFloat = 1.0) {
        var cString:String = hexFromString.trimmingCharacters(in: .whitespacesAndNewlines).uppercased()
        var rgbValue:UInt32 = 10066329 //color #999999 if string has wrong format

        if (cString.hasPrefix("#")) {
            cString.remove(at: cString.startIndex)
        }

        if ((cString.count) == 6) {
            Scanner(string: cString).scanHexInt32(&rgbValue)
        }

        self.init(
            red: CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0,
            green: CGFloat((rgbValue & 0x00FF00) >> 8) / 255.0,
            blue: CGFloat(rgbValue & 0x0000FF) / 255.0,
            alpha: alpha
        )
    }
}

更新了Swift 4

let myColor = UIColor(hexFromString: "4F9BF5")

let myColor = UIColor(hexFromString: "#4F9BF5")

let myColor = UIColor(hexFromString: "#4F9BF5", alpha: 0.5)
19
投票

Swift 4：通过UIColor支持Hex和CSS颜色名称

// Creates a UIColor from a Hex string. func colorWithHexString (hex:String) -> UIColor { var cString:String = hex.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet()).uppercaseString if (cString.hasPrefix("#")) { cString = (cString as NSString).substringFromIndex(1) } if (cString.characters.count != 6) { return UIColor.grayColor() } let rString = (cString as NSString).substringToIndex(2) let gString = ((cString as NSString).substringFromIndex(2) as NSString).substringToIndex(2) let bString = ((cString as NSString).substringFromIndex(4) as NSString).substringToIndex(2) var r:CUnsignedInt = 0, g:CUnsignedInt = 0, b:CUnsignedInt = 0; NSScanner(string: rString).scanHexInt(&r) NSScanner(string: gString).scanHexInt(&g) NSScanner(string: bString).scanHexInt(&b) return UIColor(red: CGFloat(r) / 255.0, green: CGFloat(g) / 255.0, blue: CGFloat(b) / 255.0, alpha: CGFloat(1)) }

示例字符串：

  • let color1 = colorWithHexString("#1F437C") ，func colorWithHexString (hex:String) -> UIColor { var cString = hex.trimmingCharacters(in: CharacterSet.whitespacesAndNewlines).uppercased() if (cString.hasPrefix("#")) { cString = (cString as NSString).substring(from: 1) } if (cString.characters.count != 6) { return UIColor.gray } let rString = (cString as NSString).substring(to: 2) let gString = ((cString as NSString).substring(from: 2) as NSString).substring(to: 2) let bString = ((cString as NSString).substring(from: 4) as NSString).substring(to: 2) var r:CUnsignedInt = 0, g:CUnsignedInt = 0, b:CUnsignedInt = 0; Scanner(string: rString).scanHexInt32(&r) Scanner(string: gString).scanHexInt32(&g) Scanner(string: bString).scanHexInt32(&b) return UIColor(red: CGFloat(r) / 255.0, green: CGFloat(g) / 255.0, blue: CGFloat(b) / 255.0, alpha: CGFloat(1)) } ，Gist code等
  • Orange，Lime，Tomato和空字符串产量Clear
  • Transparent
  • nil
  • [UIColor clearColor]
  • abc
  • abc7
  • #abc7

游乐场输出：

14
投票

该示例应该适用于Swift 2.2，Swift.3，Swift 3，Swift 4：

00FFFF

使用它们如下：#00FFFF

老答案

我在Swift 2.2中制作了另一个00FFFF77，它可以直接使用十六进制值来public extension UIColor { convenience init(hex: Int, alpha: Double = 1.0) { self.init(red: CGFloat((hex>>16)&0xFF)/255.0, green: CGFloat((hex>>8)&0xFF)/255.0, blue: CGFloat((hex)&0xFF)/255.0, alpha: CGFloat(255 * alpha) / 255) } convenience init(hexString: String, alpha: Double = 1.0) { let hex = hexString.trimmingCharacters(in: CharacterSet.alphanumerics.inverted) var int = UInt32() Scanner(string: hex).scanHexInt32(&int) let r, g, b: UInt32 switch hex.count { case 3: // RGB (12-bit) (r, g, b) = ((int >> 8) * 17, (int >> 4 & 0xF) * 17, (int & 0xF) * 17) case 6: // RGB (24-bit) (r, g, b) = (int >> 16, int >> 8 & 0xFF, int & 0xFF) default: (r, g, b) = (1, 1, 0) } self.init(red: CGFloat(r) / 255, green: CGFloat(g) / 255, blue: CGFloat(b) / 255, alpha: CGFloat(255 * alpha) / 255) } } ，希望可以帮助某人：

Example

并像这样使用它：

UIColor extension
13
投票

UIColor答案显示了如何在Obj-C中完成它。这座桥是用的

extension UIColor {
   convenience init(hex: Int, alpha: Double = 1.0) {
      self.init(red: CGFloat((hex>>16)&0xFF)/255.0, green:CGFloat((hex>>8)&0xFF)/255.0, blue: CGFloat((hex)&0xFF)/255.0, alpha:  CGFloat(255 * alpha) / 255)
   }
}
最新问题
© www.soinside.com 2019 - 2024. All rights reserved.