Trouble reading in text file into needed array format

I'll take a stab at this assuming that what you want to do is take the info from the text file and end up with an array of your candy products. At the moment you have your myArray class that looks a little bit like some Frankenstein thing. It contains all of the categories and names in two separate arrays inside a single instance of that class. Then you put it into an array called candies. That all looks like a dead-end unless I'm misunderstanding your requirements. (Maybe I am.) But assuming I'm at least half correct...

You want an array of candies so let's make a new class to hold a single candy.

class Candy {
    let category: String!
    let name: String!

    init(category: String, name: String) {
        self.category = category
        self.name = name
    }
}

This is similar to what you had already but when you instantiate an instance of Candy it will hold the details of a single candy. Note class names start with a capital letter by convention.

You want to end up with an array of candies so let's change the definition of your candies array.

var candies: [Candy] = []

All that's left is to change your for in loop to extract one candy's worth of data (category and name) per loop, create a new Candy instance and populate it before adding it into candies.

for (index, element) in lines_separatedBy_comma.enumerated() {
   var newCategory = ""
   var newName = ""
   if index % 2 == 0 {
      newCategory = element
   } else {
      newName = element
   }
   let newCandy = Candy(category: newCategory, name: newName)
   candies.append(newCandy)
}

You don't have any checking in your code that would handle any errors/bad formatting in your text file so I'll assume you are absolutely certain that it is composed of pairs of data with no loose ends, etc. I see you remove the last element of evenIndices for some reason. I'm not sure why so I haven't handled that.

Now your candies array should hold a bunch of Candy objects, so to list them to the console you can do something like this.

for candy in candies {
   print("category: \(String(describing: candy.category)), name: \(String(describing: candy.name))")
}

Let me know if I'm still missing the mark.

EDIT ******************************************************** EDIT

I took a look at the RW tutorial you linked.

The tutorial uses a struct for the Candy element whereas you (and I) have used a class. I guess you're still learning about Swift's value and reference types so won't muddy the water here further. Suffice to say a struct would probably be better in this instance. print also handles them differently and seems able to look inside structs for the values, whereas unless you explicitly extract the properties (as in my for in print statement, it just gives you a list of the classes as we've seen.

I've also sorted the logic (it's ugly and you shouldn't do it this way) so you can at least see that it does work (after a fashion). The whole setupArray method:

private func setupArray() {
     if let filepath = Bundle.main.path(forResource: "candyTextFile", ofType: "txt") {
         do {
             let contents = try String(contentsOfFile: filepath)
             let lines_separatedBy_n : [String] = contents.components(separatedBy: "\n")
             let string = lines_separatedBy_n.map { String($0) }.joined(separator: ", ")
             var lines_separatedBy_comma : [String] = string.components(separatedBy: ", ")

             // I've put this in to remove the last bit of the file that was causing the count to be one too high.
             // I'm guessing that's why you had something similar previously?
             lines_separatedBy_comma.removeLast()

             for (index, element) in lines_separatedBy_comma.enumerated() {
                 if index % 2 == 0 {
                     let newCategory = element
                     let newName = lines_separatedBy_comma[index + 1]
                     let newCandy = Candy(category: newCategory, name: newName)
                     candies.append(newCandy)
                 }
             }
             for candy in candies {
                 print("category: \(candy.category!), name: \(candy.name!)")
             }
             print("\ncandies: \(candies)")
         } catch let error as NSError {
             print(error.localizedDescription)
         }
     }
 }

When I use:

class Candy {
    let category: String!
    let name: String!

    init(category: String, name: String) {
        self.category = category
        self.name = name
    }
}

the output is:

category: Chocolate, name: Chocolate Bar
category: Chocolate, name: Chocolate Cookie
category: Hard, name: Lollipop

candies: [FileTest.Candy, FileTest.Candy, FileTest.Candy]

When I use: (after removing the force unwrapping from the print statement)

struct Candy {
    let category : String
    let name : String
}

the output is:

category: Chocolate, name: Chocolate Bar
category: Chocolate, name: Chocolate Cookie
category: Hard, name: Lollipop

candies: [FileTest.Candy(category: "Chocolate", name: "Chocolate Bar"), FileTest.Candy(category: "Chocolate", name: "Chocolate Cookie"), FileTest.Candy(category: "Hard", name: "Lollipop")]

Can you see that your original code placed everything inside one myArray but the code above (and on the RW site) creates individual Candy elements and stores all of them into candies? It's a fundamental difference in approaches.