Bdtjtk

I am trying to condense an application I am working on that involves a large directory with lots of UIViewControllers with UITableViews.

My plan is to rewrite the application that will use one-reusuable UIViewController with UITableView that will load in data from the txt files as needed at/after runtime. The txt files will be read at/after runtime instead of having to build all of the swift files before hand.

Currently, my application takes several minutes to build/compile everytime I make a change to the project. Therefore, I am hoping by reading and parsing the txt files as needed, I will be able to build the application within just a few seconds.

Below is my attempt to read and generate the necessary "candies" array using using the example text file provided below (candyTextFile.txt). Please see the commented lines in the class, MasterViewController, for the error message and the code that I am trying to output the candies array as.

Note, I have shortened the lines in my text file down to three lines. My final application will have many of similar text files with each one expanding several hundred lines long.

I am still relatively new to Swift so I apologize if I am missing something simple here and if I am using/not-using the appropraite terminology.

I belive the term CandySearch is just from the project name ( see here ). I am not sure why it is getting outputted though in the candies array. Also, I do see now that my current myArray is established as a class. How can I turn it into an array?

Here is my relevant code in my MasterViewController.swift,

class MasterViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {

    var candies = [myArray]()

    var evenIndicies = [String]()

    var oddIndicies = [String]()



    override func viewDidLoad() {

        super.viewDidLoad()



        setUpArray()

    }



    private func setUpArray() {

        if let filepath = Bundle.main.path(forResource: "candyTextFile", ofType: "txt") {

            do {

                // let contents = try String(contentsOfFile: "candyTextFile", encoding: String.Encoding.utf8)

                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: ", ")

                print("string: (string)")

                let lines_separatedBy_comma : [String] = string.components(separatedBy: ", ")

                print("lines_separatedBy_comma: (lines_separatedBy_comma)")



                for (index, element) in lines_separatedBy_comma.enumerated() {

                    if index % 2 == 0 {

                        evenIndicies.append(element)

                        print("evenIndicies: (evenIndicies)")



                    } else {

                        oddIndicies.append(element)

                        print("oddIndicies: (oddIndicies)")

                    }

                }

                evenIndicies.remove(at: evenIndicies.count - 1) // the -1 removes the nil element, "", in the array. For some reason, there is a fourth element, "", in the evenIndicies array. Therefore, I remove it by subtracting one index so I get the three indexes. My in project txt file is four lines long where the fourth line is empty. I think this is why it is showing up "" for the fourth index.

                print("evenIndicies outside for-loop: (evenIndicies)")

                print("oddIndicies outside for-loop: (oddIndicies)")

                candies = [myArray(category: evenIndicies, name: oddIndicies)]  // 



                print("candies: (candies)") 

           // This prints as the following:

           // candies: [CandySearch.myArray]



           // HOWEVER, I am trying to get it to print as: 

           // [CandySearch.myArray(category: "Chocolate", name: "Chocolate Bar"), CandySearch.myArray(category: "Chocolate", name: "Chocolate Cookie"), CandySearch.myArray(category: "Hard", name: "Lollipop")]









            } catch let error as NSError {

                print(error.localizedDescription)

            }

        }

    }

}



class myArray {

    let category: [String]

    let name: [String]

    init(category: [String], name: [String]) {

        self.category = category

        self.name = name

    }

}

In my text file, candyTextFile.txt, I have

Chocolate, Chocolate Bar

Chocolate, Chocolate Cookie

Hard, Lollipop

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.