Swift, CoreData: TableView not reloading data when childVC dismissed - ios

Question

Ok I am brand new to this and am a bit overwhelmed going through many tutorials and articles. And spent a few hours sorting through similar issues with no luck in fixing my own. I have a "AddSiteVC" to allow the user to add or delete Items that are put into CoreData and then displayed in a TableView on my "MainVC". My problem is when I press save or delete and get dismissed back to my MainVC onBtnClick the TableView doesn't update until I leave the MainVC and then come back. I don't know what I'm doing wrong but can't seem to find anything that fixes this... I don't know where my problem is so I'll include most of my MainVC code for reference.
Any help would be greatly appreciated!
Thanks!
import UIKit
import CoreData
class SitesViewController: UIViewController, UITableViewDelegate, UITableViewDataSource, NSFetchedResultsControllerDelegate {
#IBOutlet weak var tableView: UITableView!
var controller: NSFetchedResultsController<Sites>!
override func viewDidLoad() {
super.viewDidLoad()
tableView.delegate = self
tableView.dataSource = self
attemptFetch()
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "SitesCell", for: indexPath) as! SitesCell
configureCell(cell: cell, indexPath: indexPath as NSIndexPath)
return UITableViewCell()
}
func configureCell(cell: SitesCell, indexPath: NSIndexPath) {
let sites = controller.object(at: indexPath as IndexPath)
cell.configureCell(sites: sites)
cell.accessoryType = .detailButton
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "AddSiteViewController" {
if let destination = segue.destination as? AddSiteViewController {
if let site = sender as? Sites {
destination.siteToEdit = site
}
}
}
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
if let sections = controller.sections {
let sectionInfo = sections[section]
return sectionInfo.numberOfObjects
}
return 0
}
func numberOfSections(in tableView: UITableView) -> Int {
if let sections = controller.sections {
return sections.count
}
return 0
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 75
}
func tableView(_ tableView: UITableView, accessoryButtonTappedForRowWith indexPath: IndexPath) {
if let objs = controller.fetchedObjects, objs.count > 0 {
let site = objs[indexPath.row]
performSegue(withIdentifier: "AddSiteViewController", sender: site)
}
}
func attemptFetch() {
let fetchRequest: NSFetchRequest<Sites> = Sites.fetchRequest()
let alphebaticalSort = NSSortDescriptor(key: "name", ascending: true)
fetchRequest.sortDescriptors = [alphebaticalSort]
let controller = NSFetchedResultsController(fetchRequest: fetchRequest, managedObjectContext: context, sectionNameKeyPath: nil, cacheName: nil)
controller.delegate = self
self.controller = controller
do {
try controller.performFetch()
} catch {
let error = error as NSError
print("\(error)")
}
}
func controllerWillChangeContent(_ controller: NSFetchedResultsController<NSFetchRequestResult>) {
tableView.beginUpdates()
}
func controller(_ controller: NSFetchedResultsController<NSFetchRequestResult>, didChange anObject: Any, at indexPath: IndexPath?, for type: NSFetchedResultsChangeType, newIndexPath: IndexPath?) {
switch (type) {
case.insert:
if let indexPath = newIndexPath {
tableView.insertRows(at: [indexPath], with: .fade)
}
break
case.delete:
if let indexPath = indexPath {
tableView.deleteRows(at: [indexPath], with: .fade)
}
break
case.update:
if let indexPath = indexPath {
let cell = tableView.cellForRow(at: indexPath) as! SitesCell
configureCell(cell: cell, indexPath: indexPath as NSIndexPath)
}
break
case.move:
if let indexPath = indexPath {
tableView.deleteRows(at: [indexPath], with: .fade)
}
if let indexPath = newIndexPath {
tableView.insertRows(at: [indexPath], with: .fade)
}
break
}
}
func controllerDidChangeContent(_ controller: NSFetchedResultsController<NSFetchRequestResult>) {
tableView.endUpdates()
}
}

Answer 1

Please make following change in the code . Because viewDidLoad will be called when viewcontroller is loaded . But as per your requirement you adding something in Modal page. So you need move the code to viewWillAppear
import UIKit
import CoreData
class SitesViewController: UIViewController, UITableViewDelegate, UITableViewDataSource, NSFetchedResultsControllerDelegate {
#IBOutlet weak var tableView: UITableView!
var controller: NSFetchedResultsController<Sites>!
override func viewDidLoad() {
super.viewDidLoad()
tableView.delegate = self
tableView.dataSource = self
}
override func viewWillAppear(animated: Bool) {
super.viewWillAppear(animated)
attemptFetch()
}
}

Answer 2

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "SitesCell", for: indexPath) as! SitesCell
configureCell(cell: cell, indexPath: indexPath as NSIndexPath)
return cell }