ColorAnimation.swift

ColorAnimation.swift

private struct ColorAnimation: AnimatableModifier {

    var animatableData: Double
    private let rgbaPair: [(Double, Double)]

    init(from: Color, to: Color, percentToColor: Double) {
        animatableData = percentToColor
        let fromComponents = UIColor(from).cgColor.components!
        let toComponents = UIColor(to).cgColor.components!
        rgbaPair = Array(zip(fromComponents.map(Double.init), toComponents.map(Double.init)))
    }

    func body(content: Content) -> some View {
        content
            .foregroundColor(mixedColor)
    }

    // This is a very basic implementation of a color interpolation between two values.
    private var mixedColor: Color {
        let rgba = rgbaPair.map { $0.0 + ($0.1 - $0.0) * animatableData }
        return Color(red: rgba[0], green: rgba[1], blue: rgba[2], opacity: rgba[3])
    }

}