How to Properly Declare Array of Custom Objects in Swift?

jbd36 picture jbd36 · Jan 27, 2015 · Viewed 78.5k times · Source

Here is my custom class...not sure if I'm missing anything in it...

import UIKit

class baseMakeUp {
    var Image = UIImage()
    var Brand: String
    var Color: String
    var Rating: Int = 0

    init (Brand: String, Color: String) {
        self.Brand = Brand
        self.Color = Color
    }
}

I'm trying to instantiate here...

import UIKit

class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {

    required init(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    let cellIdentifier = "cellIdentifier"

    var foundation: [[baseMakeUp]]
    var blush: [[baseMakeUp]]
    var eyes: [[baseMakeUp]]
    var lips: [[baseMakeUp]]
    var nails: [[baseMakeUp]]

    // put some test data in makeup arrays here...
    foundation[0].Brand = "Revlon"     -------------> "Expected declaration" error.
    foundation[0].Color = "Red"
    foundation[0].Rating = 3
    foundation[1].Brand = "MAC"
    foundation[1].Color = "Blue"
    foundation[1].Rating = 4

I didn't include the rest of the ViewController class, because I didn't think it was necessary.

The error occurs when I attempt to assign a value to foundation[0].Brand

Appreciate your help in advance!

Answer

Nightly picture Nightly · Jan 27, 2015

First, I'm going to assume you didn't want 2d arrays. If you did, I'll answer your question from that perspective below.

    var foundation = [baseMakeUp]()

Creates an empty array of baseMakeUp called foundation. You can't use subscripting to add elements to an array, you can only use it to change existing elements. Since your array is empty you add elements with append.

   foundation.append(baseMakeUp(Brand: "Brand", Color: "Color"))

Since you don't have a baseMakeUp initializer that allows you to pass a rating that element's rating is 0. However since you appended it to your array you can now use subscripting to change it's Rating variable like this:

foundation[0].Rating = 3

If you did intend for 2d arrays.

    var foundation = [[baseMakeUp]]()

To create the array

    foundation.append([])
    foundation[0].append(baseMakeUp(Brand: "Brand", Color: "Color"))
    foundation[0][0].Rating = 3

The first line appends an empty array to your top level array. The second line appends a baseMakeUp to the array added in the first line. The third line uses subscripting to change the Rating of the first element in the first array of your 2d array.

Hopefully that helps with your problem.

Additionally

I was going to add points 1 and 2 from jday001s answer here, but you should check out their answer as well.

Edit

I just realized that you're trying to add elements to your arrays in the wrong scope.

You'll have to move your

foundation.append(baseMakeUp(Brand: "Brand", Color: "Color")

inside a function and call it yourself or place them inside something like viewDidLoad

eg:

class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {

    var foundation = [baseMakeUp]()

    override func viewDidLoad() {
        super.viewDidLoad()

        foundation.append(baseMakeUp(Brand: "Brand", Color: "Color")
        foundation[0].Rating = 3
    }
}

Hopefully that's helpful.