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iOS Object-Oriented Swift 2.0 Complex Data Structures Custom Initializers

Posted by James Kooi
James Kooi
879 Points

Do I need to use string interpolation to solve this problem? I have tried with and without and neither works.

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

let description: String

// Add your code below
init(red: Double = 86.0, green: Double = 191.0, 
blue: Double = 131.0, alpha: Double = 1.0, 
description: String = "red: 86.0, green: 191.0, blue: 131.0, alpha: 1.0") {

// TRIED ADDING STRING INTERPOLATION IN ABOVE LINE-- for EX: (red) in place of 86.0 but no luck!

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

    self.red = red
    self.green = green
    self.blue = blue
    self.alpha = alpha
    self.description = description
    }
}

1 Answer

Alexander Batalov
Alexander Batalov
21,887 Points
Alexander Batalov
Alexander Batalov
21,887 Points

You should not provide value for parameters like this: 

init(red: Double = 86.0, green: Double = 191.0,
         blue: Double = 131.0, alpha: Double = 1.0,
         description: String = "red: 86.0, green: 191.0, blue: 131.0, alpha: 1.0") {
// do stuff
}

By doing so I'll have to type description by myself. The point is to do it automatically. Try this instead:

init(red: Double, green: Double, blue: Double, alpha: Double) {
        // assign RGB and alpha values
        self.description = "red: \(red), green: \(green), blue: \(blue), alpha: \(alpha)"
    }
James Kooi
James Kooi
879 Points

Thank you Alex! This worked. I had tried nearly every combination and just must have missed this one. Thanks for taking the time out of your day to help me.