How to convert UIColor to hex in Swift
Here’s a simple extension to convert a UIColor
to a hex string in Swift:
extension UIColor {
func toHex() -> String {
var red: CGFloat = 0
var green: CGFloat = 0
var blue: CGFloat = 0
var alpha: CGFloat = 0
guard self.getRed(&red, green: &green, blue: &blue, alpha: &alpha) else {
assertionFailure("Failed to get RGBA components from UIColor")
return "#000000"
}
// Clamp components to be between 0 and 1
red = fmax(0, fmin(1, red))
green = fmax(0, fmin(1, green))
blue = fmax(0, fmin(1, blue))
alpha = fmax(0, fmin(1, alpha))
if alpha == 1 {
// RGB
return String(
format: "#%02lX%02lX%02lX",
Int(red * 255),
Int(green * 255),
Int(blue * 255)
)
} else {
// RGBA
return String(
format: "#%02lX%02lX%02lX%02lX",
Int(red * 255),
Int(green * 255),
Int(blue * 255),
Int(alpha * 255)
)
}
}
}
Display P3 colors are truncated to fall within the sRGB gamut.
Usage
let color = UIColor(red: 0.5, green: 0.5, blue: 0.5, alpha: 1)
print(color.toHex()) // #7F7F7F