UIColor不使用RGBA值

Question

我正在尝试使用以下代码（RGBA值）更改UITextField中的文本颜色，但它只是显示为白色或清晰，我不太确定，因为背景本身就是白色。passwordTextField.textColor = UIColor(red: CGFloat(202.0), green: CGFloat(228.0), blue: CGFloat(230.0), alpha: CGFloat(100.0))passwordTextField.returnKeyType = UIReturnKeyType.DonepasswordTextField.placeholder = "Password"passwordTextField.backgroundColor = UIColor.clearColor()passwordTextField.borderStyle = UITextBorderStyle.RoundedRectpasswordTextField.font = UIFont(name: "Avenir Next", size: 14)passwordTextField.textAlignment = NSTextAlignment.CenterpasswordTextField.secureTextEntry = true

Answer 1

UIColor的RGB值介于0和1之间（请参阅文档 “指定为0.0到1.0之间的值”）

你需要将你的数字除以255：

passwordTextField.textColor = UIColor(red: CGFloat(202.0/255.0), green: CGFloat(228.0/255.0), blue: CGFloat(230.0/255.0), alpha: CGFloat(1.0))

另外，你不需要创建CGFloats：

passwordTextField.textColor = UIColor(red:202.0/255.0, green:228.0/255.0, blue:230.0/255.0, alpha:1.0)

Answer 2

使用方便init（代码像专业人士）

步骤1

extension UIColor {

    convenience init(r: CGFloat, g: CGFloat, b: CGFloat) {

        self.init(red: r/255, green: g/255, blue: b/255, alpha: 1)

    }

}

用法

//let color = UIColor(red: 202/255, green: 228/255, blue: 230/255, alpha: 1) ☠️

let color = UIColor(r: 202, g: 228, b: 230) // ?

Answer 3

试试这个：

passwordTextField.textColor = UIColor(red: 0.792, green: 0.894, blue: 0.901, alpha: 1.0

始终放置替代值。202/255 = 0.792