Dark mode for custom SwiftUI Color - swiftui

Question

I get a series of colors with different hues from my designer. Here is how I make them
public struct Colors {
public static let blue = Blue()
public static let grey = Grey()
public static let black = Black()
public static let green = Green()
public static let orange = Orange()
public static let red = Color(hexString: "#F8454D")
public static let yellow = Color(hexString: "#FFAE03")
public init() {
}
}
public struct Blue {
public let light: Color = Color(hexString: "9AB1D0")
public let medium: Color = Color(hexString: "215499")
public let dark: Color = Color(hexString: "153662")
}
public struct Grey {
public let light: Color = Color(hexString: "CCCDD0")
public let medium: Color = Color(hexString: "757780")
public let dark: Color = Color(hexString: "404146")
}
public struct Black {
public let light: Color = Color(hexString: "A2A4A6")
public let medium: Color = Color(hexString: "33383D")
public let dark: Color = Color(hexString: "0A0B0C")
}
public struct Green {
public let light: Color = Color(hexString: "ACD3BA")
public let medium: Color = Color(hexString: "499F68")
public let dark: Color = Color(hexString: "285739")
}
public struct Orange {
public let light: Color = Color(hexString: "F4BBA5")
public let medium: Color = Color(hexString: "E76B39")
public let dark: Color = Color(hexString: "542715")
}
None of these 'Color''s respond to dark mode automatically like system provided Colors's do.
How do I assign an "inverse" color so that I can take advantage of dark mode without using system colors?

Answer 1

One way to assign an "inverse" color of your liking so that you can take advantage of dark mode without using system colors, is this:
public struct Colors {
public var blue: MyColor = Blue()
.....
public init(colorScheme: ColorScheme) {
self.blue = colorScheme == .light ? Blue() : BlueForDarkMode()
.....
}
}
public protocol MyColor {
var light: Color { get }
var medium: Color { get }
var dark: Color { get }
}
// Orange for testing
public struct BlueForDarkMode: MyColor {
public let light: Color = Color(hexString: "F4BBA5")
public let medium: Color = Color(hexString: "E76B39")
public let dark: Color = Color(hexString: "542715")
}
public struct Blue: MyColor {
public let light: Color = Color(hexString: "9AB1D0")
public let medium: Color = Color(hexString: "215499")
public let dark: Color = Color(hexString: "153662")
}
then you call it like this:
struct ContentView: View {
#Environment(\.colorScheme) var colorScheme
#State var myColors = Colors(colorScheme: .light)
var body: some View {
Rectangle()
.frame(width: 300, height: 300)
.foregroundColor(myColors.blue.medium)
.onAppear(perform: {self.myColors = Colors(colorScheme: self.colorScheme)})
}
}
Note, you will have to do a bit more work to "sense" mode changes, but that's for another question.