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iOS Object-Oriented Swift 2.0 Complex Data Structures Custom Initializers

Init

Not sure why this isn't working ...

Challenge Task 1 of 1

In the editor, I’ve declared a struct named RGBColor that models a color object in the RGB space.

Your task is to write a custom initializer method for the object. Using the initializer assign values to the first four properties. Using the values assigned to those properties create a value for the description property that is a string representation of the color object.

For example, given the values 86.0 for red, 191.0 for green, 131.0 for blue and 1.0 for alpha, each of the stored properties should hold these values and the description property should look like this:

"red: 86.0, green: 191.0, blue: 131.0, alpha: 1.0"

Note: Init methods typically list parameters in the same order of property declaration. For this task, stick to the order red,green,blue,alpha.

/Users/mattconway/Desktop/Screen Shot 2016-01-23 at 2.38.28 PM.png

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 = 86.0
self.green = 191.0
self.blue = 131.0
self.alpha = 1.0
}
}

1 Answer

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

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

You don't include the arguments with their values inside the initializer -> You include them when you're calling the initializer. The task was a bit tricky since it was giving you all those numbers but not really asking for you to include them anywhere.

More explaining about WHY the initializing is important then; Initializers