Protocol Function not being called - swift

Question

Please assist. What I'm trying to achieve
is that when I tap on a specific collectionViewCell the ReportDetailsMapController is pushed and my reports[indexPath.item] is sent from MainController to the ReportDetailsMapController.
PROTOCOL:
protocol MainControllerDelegate: class {
func sendReport(data: ReportModel)
}
FIRST VC:
class MainController: UIViewController, UICollectionViewDelegate,UICollectionViewDataSource, UICollectionViewDelegateFlowLayout {
var delegate: MainControllerDelegate?
override func viewDidLoad() {
super.viewDidLoad()
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
let report = reports[indexPath.item]
//When I print(report.name) here. Everything executes correctly
self.delegate?.sendReport(data: report)
self.navigationController?.pushViewController(ReportDetailsMapController(), animated: true)
}
}
SecondVC:
class ReportDetailsMapController: UIViewController, MainControllerDelegate {
override func viewDidLoad() {
super.viewDidLoad()
let mc = MainController()
mc.delegate = self
}
func sendReport(data: ReportModel) {
print(data.name)//This does not execute when ReportDetailsMapController is loaded.
print("Report sent")
}
}
ReportModel:
class ReportModel: NSObject {
var name: String?
var surname: String?
var cellNumber: String?
}

Answer 1

That method is not called because you didn't assign the view controller you're pushing to the delegate property.
When the cell is selected, you could do in this order: initialize the view controller and assign it to the delegate, then call the delegate method and push that view controller:
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
let report = reports[indexPath.item]
//When I print(report.name) here. Everything executes correctly
let viewController = ReportDetailsMapController()
self.delegate = viewController
self.delegate?.sendReport(data: report)
self.navigationController?.pushViewController(viewController, animated: true)
}
However, I think a simpler and more elegant way would be to simply create that property on the ReportDetailsMapController and inject it before pushing it.
There's a similar question/answer related to that here: passing data from tableview to viewContoller in swift