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iOS Object-Oriented Swift Complex Data Structures Custom Initializers

Matthew Ingram
PLUS
Matthew Ingram
Courses Plus Student 4,718 Points

Problem assigning a value to inside a struct using a custom initializer

I am confused on how I assign value to the constant description

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, description: String)
    {
        self.red = 86.0
        self.green = 191.0
        self.blue = 131.0
        self.alpha = 1.0
    }

}

3 Answers

Damien Watson
Damien Watson
27,419 Points

Hi Matthew, a few things. You don't pass in the description, you should create it in the initialiser. Also you are setting the colours to fixed numbers instead of what is passed in.

Try this:

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: \(self.red), green: \(self.green), blue: \(self.blue), alpha: \(self.alpha)"
  }
}
NIKOLA RUSEV
NIKOLA RUSEV
5,293 Points

hi damien i just want to ask you why the last property can be set just like below?

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