How to convert a HTML name string into a UIColor
Swift version: 5.2
HTML color names let you use familiar titles like "steel blue" and "mint cream" rather than hex values, but sadly these standardized names aren't available in iOS – or at least not by default. Fortunately, it's easy to add an extension to UIColor that maps these names to hexadecimal color values, then add another extension to convert hex colors to UIColors. Here's the code:
extension UIColor {
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.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
}
public convenience init?(name: String) {
let allColors = [
"aliceblue": "#F0F8FFFF",
"antiquewhite": "#FAEBD7FF",
"aqua": "#00FFFFFF",
"aquamarine": "#7FFFD4FF",
"azure": "#F0FFFFFF",
"beige": "#F5F5DCFF",
"bisque": "#FFE4C4FF",
"black": "#000000FF",
"blanchedalmond": "#FFEBCDFF",
"blue": "#0000FFFF",
"blueviolet": "#8A2BE2FF",
"brown": "#A52A2AFF",
"burlywood": "#DEB887FF",
"cadetblue": "#5F9EA0FF",
"chartreuse": "#7FFF00FF",
"chocolate": "#D2691EFF",
"coral": "#FF7F50FF",
"cornflowerblue": "#6495EDFF",
"cornsilk": "#FFF8DCFF",
"crimson": "#DC143CFF",
"cyan": "#00FFFFFF",
"darkblue": "#00008BFF",
"darkcyan": "#008B8BFF",
"darkgoldenrod": "#B8860BFF",
"darkgray": "#A9A9A9FF",
"darkgrey": "#A9A9A9FF",
"darkgreen": "#006400FF",
"darkkhaki": "#BDB76BFF",
"darkmagenta": "#8B008BFF",
"darkolivegreen": "#556B2FFF",
"darkorange": "#FF8C00FF",
"darkorchid": "#9932CCFF",
"darkred": "#8B0000FF",
"darksalmon": "#E9967AFF",
"darkseagreen": "#8FBC8FFF",
"darkslateblue": "#483D8BFF",
"darkslategray": "#2F4F4FFF",
"darkslategrey": "#2F4F4FFF",
"darkturquoise": "#00CED1FF",
"darkviolet": "#9400D3FF",
"deeppink": "#FF1493FF",
"deepskyblue": "#00BFFFFF",
"dimgray": "#696969FF",
"dimgrey": "#696969FF",
"dodgerblue": "#1E90FFFF",
"firebrick": "#B22222FF",
"floralwhite": "#FFFAF0FF",
"forestgreen": "#228B22FF",
"fuchsia": "#FF00FFFF",
"gainsboro": "#DCDCDCFF",
"ghostwhite": "#F8F8FFFF",
"gold": "#FFD700FF",
"goldenrod": "#DAA520FF",
"gray": "#808080FF",
"grey": "#808080FF",
"green": "#008000FF",
"greenyellow": "#ADFF2FFF",
"honeydew": "#F0FFF0FF",
"hotpink": "#FF69B4FF",
"indianred": "#CD5C5CFF",
"indigo": "#4B0082FF",
"ivory": "#FFFFF0FF",
"khaki": "#F0E68CFF",
"lavender": "#E6E6FAFF",
"lavenderblush": "#FFF0F5FF",
"lawngreen": "#7CFC00FF",
"lemonchiffon": "#FFFACDFF",
"lightblue": "#ADD8E6FF",
"lightcoral": "#F08080FF",
"lightcyan": "#E0FFFFFF",
"lightgoldenrodyellow": "#FAFAD2FF",
"lightgray": "#D3D3D3FF",
"lightgrey": "#D3D3D3FF",
"lightgreen": "#90EE90FF",
"lightpink": "#FFB6C1FF",
"lightsalmon": "#FFA07AFF",
"lightseagreen": "#20B2AAFF",
"lightskyblue": "#87CEFAFF",
"lightslategray": "#778899FF",
"lightslategrey": "#778899FF",
"lightsteelblue": "#B0C4DEFF",
"lightyellow": "#FFFFE0FF",
"lime": "#00FF00FF",
"limegreen": "#32CD32FF",
"linen": "#FAF0E6FF",
"magenta": "#FF00FFFF",
"maroon": "#800000FF",
"mediumaquamarine": "#66CDAAFF",
"mediumblue": "#0000CDFF",
"mediumorchid": "#BA55D3FF",
"mediumpurple": "#9370D8FF",
"mediumseagreen": "#3CB371FF",
"mediumslateblue": "#7B68EEFF",
"mediumspringgreen": "#00FA9AFF",
"mediumturquoise": "#48D1CCFF",
"mediumvioletred": "#C71585FF",
"midnightblue": "#191970FF",
"mintcream": "#F5FFFAFF",
"mistyrose": "#FFE4E1FF",
"moccasin": "#FFE4B5FF",
"navajowhite": "#FFDEADFF",
"navy": "#000080FF",
"oldlace": "#FDF5E6FF",
"olive": "#808000FF",
"olivedrab": "#6B8E23FF",
"orange": "#FFA500FF",
"orangered": "#FF4500FF",
"orchid": "#DA70D6FF",
"palegoldenrod": "#EEE8AAFF",
"palegreen": "#98FB98FF",
"paleturquoise": "#AFEEEEFF",
"palevioletred": "#D87093FF",
"papayawhip": "#FFEFD5FF",
"peachpuff": "#FFDAB9FF",
"peru": "#CD853FFF",
"pink": "#FFC0CBFF",
"plum": "#DDA0DDFF",
"powderblue": "#B0E0E6FF",
"purple": "#800080FF",
"rebeccapurple": "#663399FF",
"red": "#FF0000FF",
"rosybrown": "#BC8F8FFF",
"royalblue": "#4169E1FF",
"saddlebrown": "#8B4513FF",
"salmon": "#FA8072FF",
"sandybrown": "#F4A460FF",
"seagreen": "#2E8B57FF",
"seashell": "#FFF5EEFF",
"sienna": "#A0522DFF",
"silver": "#C0C0C0FF",
"skyblue": "#87CEEBFF",
"slateblue": "#6A5ACDFF",
"slategray": "#708090FF",
"slategrey": "#708090FF",
"snow": "#FFFAFAFF",
"springgreen": "#00FF7FFF",
"steelblue": "#4682B4FF",
"tan": "#D2B48CFF",
"teal": "#008080FF",
"thistle": "#D8BFD8FF",
"tomato": "#FF6347FF",
"turquoise": "#40E0D0FF",
"violet": "#EE82EEFF",
"wheat": "#F5DEB3FF",
"white": "#FFFFFFFF",
"whitesmoke": "#F5F5F5FF",
"yellow": "#FFFF00FF",
"yellowgreen": "#9ACD32FF"
]
let cleanedName = name.replacingOccurrences(of: " ", with: "").lowercased()
if let hexString = allColors[cleanedName] {
self.init(hexString: hexString)
} else {
return nil
}
}
}With that done, here's how you create a color:
let steelBlue = UIColor(name: "steel blue")
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Available from iOS 2.0
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