Swift 版 解析16进制颜色
extension UIColor {
public convenience init(hex: String) {
var red: CGFloat = 0.0
var green: CGFloat = 0.0
var blue: CGFloat = 0.0
var alpha: CGFloat = 1.0
var hex: String = hex
if hex.hasPrefix("#") {
let index = hex.index(hex.startIndex, offsetBy: 1)
hex = String(hex[index...])