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SOLVED: Problems extending Color

Forums > 100 Days of SwiftUI

I tried to make an extension to Color but it doesn't work in SwiftUI. I noticed that Color has the @Frozen attribute - I think that means it can't be extended. Does anyone know if there is a way to create custom named colors that can be used in SwiftUI e.g.

Color.myCustomColor
Text("Hello World")
    .foregroundColor(.myCustomColor)

1      

You can absolutely extend Color. You can do it like so:

import SwiftUI

extension Color {
    static let myCustomColor = Color(red: 0.9, green: 0.5, blue: 0.9)

    static let myCustomColor2 = Color(uiColor: .quaternaryLabel)

    static let myCustomColor3 = Color("namedColor")

    //or using any other initializer for Color
}

@frozen just means you can't add new stored instance properties to it.

1      

Thanks @roosterboy - I didn't think to try making a static constant property.

1      

You can also do it with a computed variable or a function if you need to include logic:

extension Color {
    var myCustomColor4: Color {
        if UITraitCollection.current.userInterfaceStyle == .dark {
            return .teal
        } else {
            return .cyan
        }
    }

    func myCustomColor5(userIsRegistered: Bool) -> Color {
        if userIsRegistered {
            return .green
        } else {
            return .red
        }
    }
}

2      

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