Swift UITableView messing up after reloadData() - ios

Question

I'm developing an iOS app where I want to reload information of a UITableView from a different controller. In order to do that, I have a reference of the controller MainViewController with the UITableView in another controller called (AirlinesController).
I have an issue reloading the data of the UITableView of the first controller where it messes up pretty much:
MainViewController
Each cell of the table you can see leads to AirlinesController:
AirlinesController
So after the user clicks on the "Apply" button, the UITableView of MainViewController reloads using mainView.reloadData(). In this example I would want to see in the MainViewController that the cell with the title "Embraer" has a green label with the text "Completed" and the cell with the title "Airbus" has a yellow label with the title "Employee" but this is the result I get after reloading the table:
Why did the last cell of the table change one of its labels color to yellow?
This is the code I'm using:
MainViewController
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "itemCell", for: indexPath) as! CellController
let items = self.gameView.data!.levels
cell.model.text = items[indexPath.row].name
if items[indexPath.row].id < self.gameView.game!.level.id {
cell.cost.text = "Complete"
cell.cost.textColor = UIColor.systemGreen
cell.accessoryType = .none
cell.isUserInteractionEnabled = false
} else if items[indexPath.row].id == self.gameView.game!.level.id {
cell.cost.text = "Employee"
cell.cost.textColor = UIColor.systemYellow
cell.accessoryType = .none
cell.isUserInteractionEnabled = false
} else {
cell.cost.text = "\(items[indexPath.row].XP) XP"
}
return cell
}
AirlinesController
#IBAction func apply(_ sender: Any) {
if (mainView.game.XP >= level.XP) {
let new_salary = Int(Float(mainView.game.salary) * level.salaryMultiplier)
let new_XP = Int(Float(mainView.game.XPSalary) * level.XPMultiplier)
mainView.game.salary = new_salary
mainView.game.XPSalary = new_XP
mainView.salaryLabel.text = "\(new_salary) $"
mainView.XPLabel.text = "\(new_XP) XP"
mainView.workingFor.text = "Currently working for \(level.name)"
mainView.game.level = Level(id: level.id, name: level.name, XP: 0, XPMultiplier: 1, salaryMultiplier: 1, aircrafts: [Aircraft]())
mainView.saveGame()
DispatchQueue.main.async {
self.mainView.levelItems.reloadData()
self.navigationController?.popViewController(animated: true)
}
} else {
let alert = UIAlertController(title: "Error", message: "Not enough experience to apply!", preferredStyle: UIAlertController.Style.alert)
alert.addAction(UIAlertAction(title: "OK", style: UIAlertAction.Style.cancel, handler: nil))
self.present(alert, animated: true)
}
}
How can I fix this?

Answer 1

This is because of the reuse of cells.
Set the default color in else condition.
} else {
cell.cost.textColor = UIColor.gray
cell.cost.text = "\(items[indexPath.row].XP) XP"
}
Another way, you can set the default style property inside the prepareForReuse method of UITableViewCell
class TableViewCell: UITableViewCell {
override func prepareForReuse() {
super.prepareForReuse()
// Set default cell style
}
}

Answer 2

TableViewCell are reused all the time. My advice is that you have to set the default color every time.
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "itemCell", for: indexPath) as! CellController
cell.cost.textColor = ...your default text color....
...
return cell