swift - How to get RGB components from Color in SwiftUI

Question

If I have a SwiftUI Color:

let col: Color = Color(red: 0.5, green: 0.5, blue: 0.5)

How do I get the RGB components from col?
Like this maybe:

print(col.components.red)

In UIKit, I could use UIColor.getRed but there doesn't seem to be an equivalent in SwiftUI.

Answer 1

iOS 14 / macOS 10.16

There is a new initializer that takes a Color and returns a UIColor for iOS or NSColor for macOS now. With the help of those you can implement the following extensions:

iOS / macOS

import SwiftUI

#if canImport(UIKit)
import UIKit
#elseif canImport(AppKit)
import AppKit
#endif

extension Color {
    var components: (red: CGFloat, green: CGFloat, blue: CGFloat, opacity: CGFloat) {

        #if canImport(UIKit)
        typealias NativeColor = UIColor
        #elseif canImport(AppKit)
        typealias NativeColor = NSColor
        #endif

        var r: CGFloat = 0
        var g: CGFloat = 0
        var b: CGFloat = 0
        var o: CGFloat = 0

        guard NativeColor(self).getRed(&r, green: &g, blue: &b, alpha: &o) else {
            // You can handle the failure here as you want
            return (0, 0, 0, 0)
        }

        return (r, g, b, o)
    }
}

---

Usage

Color.red.components.red // 0.9999999403953552 // <- SwiftUI Colors are not pure!