Passing data between an object class and a ViewController (Swift) - ios

Question

[WHAT I WANT] I want to develop a functionality that when I click on a button of an initial ViewController named BdaysVC (first image) a table view appears (second image) and when I click on a row of the tableView it goes back to the ViewController passing the activeSortingMode value. If I click on the opaque view it only dismisses the tableView without passing any value.
[WHAT I HAVE] The code that I have used to implement the tableView is:
class SortTableView: NSObject, UITableViewDelegate, UITableViewDataSource {
...
func createViews (frame:CGRect) {
// Creating an opaque view and a tableView and adding them above the BdaysVC
}
...
#objc func onClickTransparentView() {
// Dismissing the tableView when touching the opaque view
}
...
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
...
switch indexPath.row {
case 0:
// Change the activeSortingMode of BdaysVC to 0
case 1:
// Change the activeSortingMode of BdaysVC to 1
case 2:
// Change the activeSortingMode of BdaysVC to 2
case 3:
// Change the activeSortingMode of BdaysVC to 3
default:
print("sorting mode")
}
}
...
override init() {
super.init()
...
tableView.delegate = self
tableView.dataSource = self
...
}
}
And for the ViewController:
class BdaysVC: UIViewController {
...
var activeSortingMode: Int = 0
...
let sortTableView = SortTableView()
#IBAction func sortButtonClicked(_ sender: Any) {
sortTableView.createViews(frame: self.view.frame)
}
override func viewWillAppear(_ animated: Bool) {
...
retrieveSections(sortingMode: activeSortingMode)
}
override func viewDidLoad() {
super.viewDidLoad()
...
retrieveSections(sortingMode: activeSortingMode)
}
}
[PROBLEM] My problem is that I don't know how to change the activeSortingMode value of the ViewController when a cell of the tableView is selected and reload the ViewController with the method viewWillAppear().
I hope you can help me with this issue. Thanks in advance!

Answer 1

You can use delegate or closure for that
protocol ActiveSortingModeSelect {
func activeSortingModeSelected(_ index: Int)
}
class SortTableView: NSObject, UITableViewDelegate, UITableViewDataSource {
...
weak var delegate: ActiveSortingModeSelect!
func createViews (frame:CGRect) {
// Creating an opaque view and a tableView and adding them above the BdaysVC
}
...
#objc func onClickTransparentView() {
// Dismissing the tableView when touching the opaque view
}
...
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
...
delegate.activeSortingModeSelected(indexPath.row)
...
override init() {
super.init()
...
tableView.delegate = self
tableView.dataSource = self
...
}
}
class BdaysVC: UIViewController {
...
var activeSortingMode: Int = 0
...
let sortTableView = SortTableView()
#IBAction func sortButtonClicked(_ sender: Any) {
sortTableView.createViews(frame: self.view.frame)
}
override func viewWillAppear(_ animated: Bool) {
...
retrieveSections(sortingMode: activeSortingMode)
}
override func viewDidLoad() {
super.viewDidLoad()
...
sortTableView.delegate = self // Don't forget to set delegate
retrieveSections(sortingMode: activeSortingMode)
}
}
extension BdaysVC: ActiveSortingModeSelect {
func activeSortingModeSelected(_ index: Int) {
self.activeSortingMode = index
}
}