How to pass data between two view controllers, indexPathForSelectedRow swift3?

Question

iOS

Hello, friends. I have an error in passing data between two view controllers.
The "TheChoiseOfShipTableViewController" stores data in a class:

let ships: [Ships] = [
        Ships(name: "Сухогрузное судно общего назначения", image: "Сухогрузное судно общего назначения.png"),
        Ships(name: "Морское рефрижераторное судно", image: "Морское рефрижераторное судно.png")
]

They need to be passed to the "CalculateViewController", there is such an implementation:

var ships: Ships!

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let identifier = "Cell"
        let cell = tableView.dequeueReusableCell(withIdentifier: identifier, for: indexPath) as! DetailsTableViewCell
    
        //отображение информации в ячейках
        switch indexPath.row {
        case 0:
            cell.keyLabel.text = "Название"
            cell.valueLabel.text =ships.name
        default:
            cell.keyLabel.text = ""
            cell.valueLabel.text = ""
        }
        
        return cell
    }

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        if segue.identifier == "showDetails" {
            if let destination = segue.destination as? TheChoiseOfShipTableViewController {
                let indexPath = CalculateViewController.indexPathForSelectedRow!
                destination.ships = self.ships[indexPath.row]
            }
        }
    }

The error is that it swears at ships..name, because it is equal to nil. I need to pass data, but I have an error in indexPathForSelectedRow. Tell me how to competently implement the last piece of code for data transfer.

Answer 1

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        if segue.identifier == "showDetails" {
            if let destination = segue.destination as? TheChoiseOfShipTableViewController,
               let cell = sender as? UITableViewCell,
               let indexPath = tableView.indexPath(for: cell) {
                destination.ships = self.ships[indexPath.row]
            }
        }
    }

Answer 2

swears at ships..name because it is equal to nil.

Probably because you didn't complete it. How do you pass ships..name to CalculateViewController ?