例如,下面的代码可与UIColor.Purple或UIColor.Yellow配合使用,但是当我使用UIColor.black时,应用程序崩溃。
致命错误:索引超出范围 当使用UIColor.black时,components [2]和[3]似乎不存在。我知道我要用力打开包装,但不是所有颜色都应具有RGBA吗?
//UIColor RGBA to string
public extension UIColor {
class func StringFromUIColor(color: UIColor) -> String{
let components = color.cgColor.components
return "[\(components![0]), \(components![1]), \(components![2]), \(components![3])]"
}
class func UIColorFromString(string: String) -> UIColor {
let componentsStringStepOne = string.replacingOccurrences(of: "[", with: "")
let componentsString = componentsStringStepOne.replacingOccurrences(of: "]", with: "")
let components = componentsString.components(separatedBy: ", ")
return UIColor(red: CGFloat((components[0] as NSString).floatValue), green: CGFloat((components[1] as NSString).floatValue), blue: CGFloat((components[2] as NSString).floatValue), alpha: CGFloat((components[3] as NSString).floatValue))
}
}
还有更好的方法来编写这部分代码吗?
let componentsStringStepOne = string.replacingOccurrences(of: "[", with: "")
let componentsString = componentsStringStepOne.replacingOccurrences(of: "]", with: "")
let components = componentsString.components(separatedBy: ", ")
任何帮助都值得赞赏!谢谢。
答案 0 :(得分:0)
这是我根据rmaddy和kamran响应提出的解决方案。它不会崩溃的应用程序,我得到正确的颜色。它在plist中保存了我希望它是黑色还是彩色的外观。 [0.2,0.4,0.5,1.0]。 感谢您的帮助
public extension UIColor {
class func StringFromUIColor(color: UIColor) -> String{
let components = color.cgColor.components
if components?.count == 2 {
return "[\(components![0]), \(components![0]), \(components![0]), \(components![1])]"
} else {
return "[\(components![0]), \(components![1]), \(components![2]), \(components![3])]"
}
}
class func UIColorFromString(string: String) -> UIColor {
let componentsStringStepOne = string.replacingOccurrences(of: "[", with: "")
let componentsString = componentsStringStepOne.replacingOccurrences(of: "]", with: "")
let components = componentsString.components(separatedBy: ", ")
if components.count == 2 {
return UIColor(white: CGFloat((components[0] as NSString).floatValue), alpha: CGFloat((components[1] as NSString).floatValue))
} else {
return UIColor(red: CGFloat((components[0] as NSString).floatValue), green: CGFloat((components[1] as NSString).floatValue), blue: CGFloat((components[2] as NSString).floatValue), alpha: CGFloat((components[3] as NSString).floatValue))
}
}
}