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iOS Object-Oriented Swift Complex Data Structures Custom Initializers

Carlos Glez
Carlos Glez
349 Points
Posted by Carlos Glez
Carlos Glez
349 Points

I cannot figure this out, how do you do it?

Here is the code:

struct RGBColor { let red: Double let green: Double let blue: Double let alpha: Double

let description: String

// Add your code below

init(red: Double, green: Double, blue: Double, alpha: Double) {
    self.red = red
    self.green = green
    self.blue = blue
    self.alpha = alpha
}

func RGB() -> String {
    let description = "red: \(red), green: \(green), blue: \(blue), alpha: \(alpha)"
    return description
}

}

let color = RGBColor(red: 86.0, green: 191.0, blue: 131.0, alpha: 1.0)

let description = color.RGB()

structs.swift 
struct RGBColor {
    let red: Double
    let green: Double
    let blue: Double
    let alpha: Double

    let description: String

    // Add your code below

    init(red: Double, green: Double, blue: Double, alpha: Double) {
        self.red = red
        self.green = green
        self.blue = blue
        self.alpha = alpha
    }

    func RGB() -> String {
        let description = "red: \(red), green: \(green), blue: \(blue), alpha: \(alpha)"
        return description
    }
}

let color = RGBColor(red: 86.0, green: 191.0, blue: 131.0, alpha: 1.0)

let description = color.RGB()

2 Answers

Sara Worth
Sara Worth
5,225 Points
Sara Worth
Sara Worth
5,225 Points

They want you to initialize description in the init() method, like so:

struct RGBColor {
    let red: Double
    let green: Double
    let blue: Double
    let alpha: Double

    let description: String

    init(red: Double, green: Double, blue: Double, alpha: Double) {
        self.red = red
        self.green = green
        self.blue = blue
        self.alpha = alpha

        description = "red: \(red), green: \(green), blue: \(blue), alpha: \(alpha)"
    }

}

let color = RGBColor(red: 86.0, green: 191.0, blue: 131.0, alpha: 1.0)

let description = color.description
Carlos Glez
Carlos Glez
349 Points
Carlos Glez
Carlos Glez
349 Points

Great thank you, why do you add the description inside the init? That is the only thing I don't understand. And why don't you declare description inside the init(xxxxx)? Thank you