Override func tableview runs after - ios

Question

Edit: mentioned at the bottom I was using another stackoverflow question for guidance. Turns out its the same issue that I don't believe ever got solved after the person edited their question. So I copied the exact same issue into my code: How to know which cell was tapped in tableView using Swift
There's probably many things wrong with my code at this point, but the main issue is the very edit at the bottom of the post this author puts on his question. I know that makes this a duplicate then but no one has answered that. All the accepted answers have the same outcome as my issue.
I'm very new to swift and I'm creating a flashcard type app where tapping on a tableview cell for details shows a term and definition. These terms and definitions are stored in two parallel arrays and the index is supposed to be the indexPath.row.
My issue is that int selectedCell which should be the index of the array for whichever cell the user taps always runs the code to display the term and definition before running the code to find the selected cell.
My earlier error before this was that if I made selected cell an optional (var selectedCell: Int?), the program would crash because its nil. To fix that, I made it var selectedCell: Int = 0 and that worked until I realized that no matter what I tap, the first selectedCell will always be 0.
How can I get the selectedCell before the terms and definitions are displayed.
This is the code inside CardViewController, the controller brought up after the user touches a cell for details. There are only two labels (term and definition) so the code is pretty scarce here.
override func viewDidLoad() {
super.viewDidLoad()
// Testing
print("new selectedCell: \(selectedCell)")
// Update labels for term and definition
termLabel.text = "Term: \n" + cards[selectedCell]
definitionLabel.text = "Definition: \n" + details[selectedCell]
}
The code inside CardTableViewController where the very last override func is what gives me the selectedCell. I have checked that the number is correct when tapped, it just runs after cardviewcontroller apparently.
This is the code for CardTableViewController, where it is tableview cells of each term from the flashcard listed.
Not to be confused with CardViewController which is the little detail flashcard screen that pops up
import UIKit
var cards = [String]()
var details = [String]()
var newCard:String = ""
var newDetail:String = ""
var study = [String]()
var selectedCell: Int = 0
class CardTableViewController: UITableViewController {
#IBOutlet var createCardButton: UIBarButtonItem!
override func viewDidLoad() {
super.viewDidLoad()
}
override func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return cards.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cardCell", for: indexPath)
cell.textLabel?.text = cards[indexPath.row]
return cell
}
#IBAction func cancel(segue:UIStoryboardSegue) {
}
#IBAction func create(segue:UIStoryboardSegue) {
let addCard = segue.source as! AddCardViewController
newCard = addCard.term
newDetail = addCard.definition
print("term: \(addCard.term)")
print("definition: \(addCard.definition)")
cards.append(newCard)
details.append(newDetail)
study.append(newCard)
tableView.reloadData()
}
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
selectedCell = indexPath.row
print("selectedCell: ", selectedCell)
}
}
I know it's out of order because of the print statements I put in. Instead, selectedCell should print before new selectedCell. Notice how new selectedCell will be 0 due to initialization (nil if I didn't initialize it) and then is always lagging one cell touch behind what it should be?
the segues for cancel and create are bar button items on the (details of the flashcard screen). They are unwind segues that I followed some online tutorial on for how to create an text field and unwind.
for background on the addCardViewController and unwind segues, this is the code inside that:
class AddCardViewController: UIViewController {
#IBOutlet weak var cardTerm: UITextField!
#IBOutlet weak var cardDefinition: UITextField!
var term:String = ""
var definition:String = ""
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "createSegue" {
term = cardTerm.text!
definition = cardDefinition.text!
}
}
Here's the printing results for the cell indexes
new selectedCell: 0
selectedCell: 0
new selectedCell: 0
selectedCell: 1
new selectedCell: 1
selectedCell: 1
Honestly not sure if there's a way to call that function first or if I'm choosing the selectedCell wrong (I got the idea off another post on stack overflow: How to know which cell was tapped in tableView using Swift)
Storyboard for my app. Shows the list of cards tableview controller and the card view controller:

Answer 1

So in my storyboard, I set up two ViewControllers (CardsTableViewController and CardViewController)
The segue in between these two view controllers is called CardSegue and is set up to present modally.
The reuse identifier for the prototype UITableViewCell in CardsTableViewController is CardCell.
This is how the CardsTableViewController looks like:
import UIKit
struct Card {
let term: String
let definition: String
}
class CardsTableViewController: UITableViewController {
var selectedCell: Int = 0
let cards: [Card] = [Card(term: "Привет", definition: "Hello"), Card(term: "Да", definition: "Yes")]
override func viewDidLoad() {
super.viewDidLoad()
}
// MARK: - Table view data source
override func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return cards.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "CardCell", for: indexPath)
cell.textLabel?.text = cards[indexPath.row].term
return cell
}
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
selectedCell = indexPath.row
performSegue(withIdentifier: "CardSegue", sender: self)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if let vc = segue.destination as? CardViewController {
let selectedCard = cards[selectedCell]
vc.card = selectedCard
vc.selectedCell = selectedCell
}
}
}
This is the CardViewController:
import UIKit
class CardViewController: UIViewController {
var card: Card = Card(term: "<Set me>", definition: "<Set me>")
var selectedCell: Int = 0
#IBOutlet weak var termLabel: UILabel!
#IBOutlet weak var definitionLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
// Testing
print("new selectedCell: \(selectedCell)")
termLabel.text = "Term: \n" + card.term
definitionLabel.text = "Definition: \n" + card.definition
}
}
I created a Card struct which has a term and a definition, both being Strings.
I created an array of two Cards with two Russian words. This is the data we're working with.
In didSelectRowAt indexPath, I have set up the same setting of "selectedCell", which is defined at the top.
Directly after, I call performSegue, which will send the user to the CardViewController, which will display the term and the definition.
The prepare(for segue) method is always called whenever performSegue is called. In the view controller, if you start typing..."prepare(for...." Xcode will probably fill it out for you.
In this method, I get the selected card, and I pass the card to the CardViewController. In this example, I pass selectedCell, but I don't know if it's really necessary, it depends on what you are trying to achieve, I guess.
This is how the two view controllers should be communicating.
Here's some good information about how to pass information from one view controller to the next: See this section: Passing Data Between View Controllers Using Segues