Passing access from tableViewController to another view controller - swift

Question

I have spent a fair bit of time on this and still can't seem to figure out what I'm doing wrong.
I would like to run the reloadData() function in my own function on another view controller than the tableViewController but I get the error Type 'HomeViewController' has no member 'reloadData'.
HomeViewController:
import UIKit
import CoreData
class HomeViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
var index = ""
var item : [ListItem] = [] //listName
var listName = [""]
override func viewDidLoad() {
super.viewDidLoad()
self.homeListsTableView.delegate = self
self.homeListsTableView.dataSource = self
homeListsTableView.reloadData()
//List Names
//List Items - Within a list Name
let listItem1 = ListItem()
listItem1.name = "" //Update so names are updated via append the ListItem Array
listItem1.location = ""
item.append(listItem1)
let listItem2 = ListItem()
listItem2.name = ""
listItem2.location = ""
item.append(listItem2)
}
#IBOutlet weak var homeListsTableView: UITableView!
#IBAction func templatesButton(_ sender: Any) {
tabBarController?.selectedIndex = 2
}
override func viewWillAppear(_ animated: Bool) {
if let context = (UIApplication.shared.delegate as? AppDelegate)?.persistentContainer.viewContext {
if let coreDataListItems = try? context.fetch(ListName.fetchRequest()) as? [ListName] {
print(coreDataListItems)
}
}
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return listName.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)
cell.textLabel?.text = listName[indexPath.row]
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
// performSegue(withIdentifier: "goToItems", sender: self)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let vc = segue.destination as! ListNameViewController
vc.homeListsTableViewVC = homeListsTableView
}
}
ListName View Controller:
import UIKit
import CoreData
class ListNameViewController: UIViewController, UITableViewDelegate {
// var listName = [""]
let context = (UIApplication.shared.delegate as? AppDelegate)?.persistentContainer.viewContext
var homeListsTableViewVC = HomeViewController.self
override func viewDidLoad() {
super.viewDidLoad()
}
#IBOutlet weak var listNameValue: UITextField!
#IBOutlet weak var locationOption: UITextField!
#IBOutlet weak var createButtonChange: UIButton!
#IBAction func createButton(_ sender: Any) {
let newList = ListName(context: context!)
newList.listName = listNameValue.text
// let location = locationOption.text!
//tabBarController?.selectedIndex = 0
//performSegue(withIdentifier: "home", sender: nil)
}
func saveList() {
do {
try context!.save()
} catch {
print("Error saving context \(error)")
}
homeListsTableViewVC.reloadData()
}
}
I'm trying to use the prepare for segue function to pass the homeListsTableView data to then use the reloadData() function. Could someone tell me what I'm doing wrong?
Thanks!

Answer 1

You can use delegate or closure to update your tableview.. here is pointers of how you can use closure in your classes to update view
class ListNameViewController: UIViewController, UITableViewDelegate {
var callback: (()->())?
//....
func saveList() {
do {
try context!.save()
} catch {
print("Error saving context \(error)")
}
callback?()
}
}
And while creating ListNameViewController
class HomeViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let vc = segue.destination as! ListNameViewController
vc.callback = { [weak self] in
self?.homeListsTableView.reloadData()
}
}
}