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iOS Object-Oriented Swift Complex Data Structures Custom Initializers

Sebastian Sigurðarson
Sebastian Sigurðarson
1,274 Points

I really don't understand what I'm supposed to do here, mostly because I don't know what to do with the 'description'

This is what I'm supposed to do.

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"

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

  let description: String

  // Add your code below
}

1 Answer

David Papandrew
David Papandrew
8,386 Points

See code below, but the gist of what you need to do is create an initializer method that takes arguments for red, green, blue and alpha. Init method will set the struct properties of the same name with the values provided by the init method. Description will also be set based on arguments sent to initializer.

Hope that helps.

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

        description = "red: \(red), green: \(green), blue: \(blue), alpha: \(alpha)"
    }
}
Sebastian Sigurðarson
Sebastian Sigurðarson
1,274 Points

Ahhhhhh yes of course, Thank you. Much appreciated :)