Getting data from the selected cell (TableView) - swift

Question

I have a TableView with several cells of data and there are 3 labels in each cell.
How can I save all 3 label.text into another variable with indexPath
let indexPath = self.tableView.indexPathForSelectedRow
Here is the full code
I've actually asked in another post that the variable "limit" becomes null after the .observe thing.
So I'm thinking if I can get the data directly from the cell.
import UIKit
import Firebase
import FirebaseDatabase
struct limitStruct{
var name : String!
var today : String!
var limit : String!
}
class CalcViewController: UITableViewController {
var limits = [limitStruct]()
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
navigationController?.navigationBar.barTintColor = UIColor.black
self.title = "Calculation"
navigationController!.navigationBar.titleTextAttributes =
[NSForegroundColorAttributeName: UIColor.white]
let databaseReference = FIRDatabase.database().reference()
databaseReference.child("Limit").queryOrderedByKey().observe(.childAdded, with: {
snapshot in
var snapshotValue = snapshot.value as? NSDictionary
let name = snapshotValue!["name"] as? String
snapshotValue = snapshot.value as? NSDictionary
let today = snapshotValue!["today"] as? String
snapshotValue = snapshot.value as? NSDictionary
let limit = snapshotValue!["limit"] as? String
snapshotValue = snapshot.value as? NSDictionary
self.limits.insert(limitStruct(name:name, today:today, limit: limit), at: self.limits.count)
self.tableView.reloadData()
})
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return limits.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Limit")
let label1 = cell?.viewWithTag(1) as! UILabel
label1.text = limits[indexPath.row].name
let label2 = cell?.viewWithTag(2) as! UILabel
label2.text = limits[indexPath.row].today
let label3 = cell?.viewWithTag(3) as! UILabel
label3.text = limits[indexPath.row].limit
return cell!
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "showDetails"{
let svc = segue.destination as! CirSliderViewController;
if let indexPath = self.tableView.indexPathForSelectedRow{
// svc.RsegueData =
}
}
}
}

Answer 1

You really don't want to be using viewWithTag(). The best way to handle this is to subclass UITableViewCell, with a property for your data model object
class LimitCell: UITableViewCell {
var limit: Limit {
didSet {
// configureCell()
}
}
}
Then in your view controller:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Limit", forIndex: indexPath) as! LimitCell
cell.limit = limits[indexPath.row]
return cell
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if let svc = segue.destination as? CirSliderViewController, cell = sender as? LimitCell {
svc.RsegueData = cell.limit
}
}

Answer 2

It seems that you are using a callback to get the data. Does the data come from a server or is stored locally?
1) If the data comes from a server, you code cannot guarantee that var limits already got the data when the func prepare is called.
2) If the data is stored locally, and ONLY limitis nil, you must check whether or not you correctly assign limits[indexPath.row].limit to limits to the cell.(Is it nil at this moment?) I think the problem is in func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) where limit is saved.
By the way, the more practical and efficient way to implement func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) is that:
Lets say the your custom cell is call LimitCell and has three UILabels: var label1, var label2, var label3.
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Limit") as! LimitCell
cell.label1.text = limits[indexPath.row].name
cell.label2.text = limits[indexPath.row].today
cell.label3.text = limits[indexPath.row].limit
return cell
}