Prepare for segue inside of for loop - ios

Question

I have a table view with the following willSelectRowAt code:
func tableView(_ tableView: UITableView, willSelectRowAt indexPath: IndexPath) -> IndexPath? {
for n in 0...carsArray.count - 1 {
if indexPath.row == n {
print(carsArray[n].name)
func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "goToEditCar" {
let name = carsArray[n].name
print(name)
let indexCar = n
let destinationVC = segue.destination as! EditCarViewController
destinationVC.name = name
destinationVC.indexCar = indexCar
}
}
performSegue(withIdentifier: "goToEditCar", sender: self)
}
}
}
Somehow the prepare function won't pass the desired data, neither will it print(name) - can anyone tell me the issue with this piece of code?

Answer 1

Your code cannot work at all. You are using the wrong API, prepare(for is never going to be called inside another method and actually you don't need a loop.
willSelectRowAt is to control if a cell is allowed to be selected. Return the indexPath if it's allowed otherwise return nil
This is not what you want. Use didSelect and pass the index path as sender when calling performSegue
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
performSegue(withIdentifier: "goToEditCar", sender: indexPath)
}
In prepare(for get the index path from the sender parameter
func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "goToEditCar" {
let indexPath = sender as! IndexPath
let name = carsArray[indexPath.row].name
print(name)
let destinationVC = segue.destination as! EditCarViewController
destinationVC.name = name
destinationVC.indexCar = indexPath.row
}
}

Answer 2

You don't need a for-loop here as n eventually will be equal to indexPath.row also you should use didSelectRowAt
func tableView(_ tableView: UITableView,didSelectRowAt indexPath: IndexPath) {
performSegue(withIdentifier: "goToEditCar", sender:indexPath.row)
}
func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "goToEditCar" {
let index = sender as! Int
let destinationVC = segue.destination as! EditCarViewController
destinationVC.name = carsArray[index].name
destinationVC.indexCar = index
}
}