Passing coredata from tableview to another tableview - ios

Question

I am struggling with getting my care data to populate my second tableview controller. The data is populating the first tableview and I can select a row and the segue is used to go to the second table but the labels are not populated.
I've looked all over and have found older samples or obj-c but I cannot figure it out, so any help pointing this n00b in the right direction will be helpful.
Here is what I have, I think I am missing how to populate a variable to pass in prepareForSegue in the list tableview, but I could be wrong. I get a warning error in that function (Warning cannot assign value of type 'ListEntity' to type '[ListEntity]').
CoreData
Entity = ListEntity
Attributes = title, event & location (all as Strings)
listTableViewController
import UIKit
import CoreData
class ListTableViewController: UITableViewController {
let managedObjectContext = (UIApplication.sharedApplication().delegate as! AppDelegate).managedObjectContext
var lists = [ListEntity]()
override func viewDidLoad() {
super.viewDidLoad()
self.title = "The List"
let addButton = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.Add, target: self, action: #selector(ListTableViewController.addButtonMethod))
navigationItem.rightBarButtonItem = addButton
}
func addButtonMethod() {
print("Perform action")
}
override func viewWillAppear(animated: Bool) {
super.viewWillAppear(animated)
reloadData()
tableView.reloadData()
}
func reloadData() {
let fetchRequest = NSFetchRequest(entityName: "ListEntity")
do {
if let results = try managedObjectContext.executeFetchRequest(fetchRequest) as? [ListEntity] {
lists = results
}
} catch {
fatalError("There was an error fetching the list!")
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
// MARK: - Table view data source
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return lists.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("ListCell") as! ListTableViewCell
let list = lists[indexPath.row]
cell.configurationWithSetup(list)
return cell
}
override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
performSegueWithIdentifier("DetailsSegue", sender: self)
tableView.deselectRowAtIndexPath(indexPath, animated: true)
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "DetailsSegue" {
let destinationVC = segue.destinationViewController as! DetailsTableViewController
let indexPath : NSIndexPath = self.tableView.indexPathForSelectedRow!
print(indexPath.row) // Print the Row selected to console
// Place the code to pass data here?
// destinationVC.lists = lists[indexPath.row]
// Warning cannot assign value of type 'ListEntity' to type '[ListEntity]'
}
}
}
listTableViewCell
import UIKit
class ListTableViewCell: UITableViewCell {
#IBOutlet weak var titleLabel: UILabel!
func configurationWithSetup(list: AnyObject) {
titleLabel.text = list.valueForKey("title") as! String?
}
}
detailsTableViewController
import UIKit
import CoreData
class DetailsTableViewController: UITableViewController {
let managedObjectContext = (UIApplication.sharedApplication().delegate as! AppDelegate).managedObjectContext
var lists = [ListEntity]()
override func viewDidLoad() {
super.viewDidLoad()
}
// MARK: - Table view data source
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 1
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("DataCell") as! DetailsTableViewCell
let list = lists[indexPath.row]
cell.configurationWithSetup(list)
return cell
}
}
detailsTableViewCell
import UIKit
import CoreData
class DetailsTableViewCell: UITableViewCell {
#IBOutlet weak var titleLabel: UILabel!
#IBOutlet weak var eventLabel: UILabel!
#IBOutlet weak var locationLabel: UILabel!
func configurationWithSetup(list: AnyObject) {
titleLabel.text = list.valueForKey("title") as! String?
eventLabel.text = list.valueForKey("event") as! String?
locationLabel.text = list.valueForKey("location") as! String?
}
}

Answer 1

The warning contains the answer - just change
var lists = [ListEntity]() to
var lists = ListEntity(), or var lists:ListEntity! and when you prepare for segue set that value.
Then you will need to change
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("DataCell") as! DetailsTableViewCell
// as data source is not array you can just you the item you passed
// let list = lists[indexPath.row]
cell.configurationWithSetup(lists)
return cell
}
You should use a static table view if you just want one cell
More info per you current issue
class DetailsTableViewController: UITableViewController {
let managedObjectContext = (UIApplication.sharedApplication().delegate as! AppDelegate).managedObjectContext
var theDetailListEntity:ListEntity!
override func viewDidLoad() {
super.viewDidLoad()
print(theDetailListEntity) // check that you passed it across
}
// MARK: - Table view data source
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 1
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("DataCell") as! DetailsTableViewCell
cell.configurationWithSetup(theDetailListEntity)
return cell
}
}
Don't forget to add prepare for segue in the listTableViewController otherwise theDetailListEntity won't be set... and then it will crash.
Depending on how you set up your segue, it may differ. But this is what you need
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
performSegueWithIdentifier("showMyDetailView", sender: indexPath)
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "showMyDetailView" {
guard let
vc = segue.destinationViewController as? DetailsTableViewController,
ip = sender as? NSIndexPath else { fatalError() }
let item = lists[ip.row]
vc.theDetailListEntity = item
// set the item in the next VC
tableView.deselectRowAtIndexPath(ip, animated: true)
}
}