Swift 3 - Setting variable in TableViewController swift file depending on cell clicked - ios

Question

I'm trying to set the a string depending on which cell in a tableView is clicked. The BlueLineTableViewController is the one which should capture the user's click.
import UIKit
class BlueLineTableViewController: UITableViewController {
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
override func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return bluelinestations.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "bluelinecell", for: indexPath)
let station = bluelinestations[indexPath.row]
cell.textLabel?.text = station.name
cell.imageView?.image = UIImage(named: station.image)
return cell
}
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let row = indexPath.row
if row == 0 {
BlueBelmontTableViewController().feed = "http://lapi.transitchicago.com/api/1.0/ttarrivals.aspx?key=mykey&mapid=40890&outputType=JSON"
}
if row == 1 {
BlueBelmontTableViewController().feed="http://lapi.transitchicago.com/api/1.0/ttarrivals.aspx?key=mykey&mapid=40820&outputType=JSON"
}
}
The BlueBelmontTableViewController's feed variable should change/be set to another url depending on which cell is clicked in the BlueLineTableViewController.
import UIKit
class BlueBelmontTableViewController: UITableViewController {
class Destinations {
var destination: String = ""
var time: String = ""
}
var feed = ""
var dataAvailable = false
var records = [Destinations]()
override func viewDidLoad() {
super.viewDidLoad()
parseData()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
for r in records {
r.time = ""
r.destination = ""
}
}
override func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return dataAvailable ? records.count : 15
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if (dataAvailable) {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)
let destinationRow = records[indexPath.row]
cell.textLabel?.text = destinationRow.destination
cell.detailTextLabel?.text = destinationRow.time
return cell
} else {
let cell = tableView.dequeueReusableCell(withIdentifier: "PlaceholderCell", for: indexPath)
return cell
}
}
func parseData() {
guard let feedURL = URL(string: feed) else {
return
}
let request = URLRequest(url: feedURL)
let task = URLSession.shared.dataTask(with: request) {(data, response, error) in
if error != nil
{
print("Error")
}
else {
if let content = data {
do {
let json = try JSONSerialization.jsonObject(with: content, options: []) as? [String:Any] ?? [:]
print(json)
if let ctattimetable = json["ctatt"] as? [String:Any] {
if let estArrivalTime = ctattimetable["eta"] as? [[String:Any]] {
for item in estArrivalTime{
if let headingTowards = item["destNm"] as? String,
let arrivalTime = item["arrT"] as? String {
let record = Destinations()
record.destination = headingTowards
record.time = arrivalTime
self.records.append(record)
}
self.dataAvailable = true
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
}
}
}
catch {
}
}
}
}
task.resume()
}
}
I've tried setting the url in the didSelectRowAt method depending on the indexPath.row as can be seen in BlueLineTableViewController, but it does not seem to do anything. Does anybody know how I would go about doing this?
Below is the Main.storyboard of this part of my project:

Answer 1

Your are not able to pass value because you are setting feed property to the completely new instance of BlueBelmontTableViewController not the one that is added in navigation stack using your segue that you have created from your UITableViewCell to BlueBelmontTableViewController.
What you need to do is override prepareForSegue in your BlueLineTableViewController to pass your value to BlueBelmontTableViewController.
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let vc = segue.destination as! BlueBelmontTableViewController
if let indexPath = self.tableView.indexPathForSelectedRow {
if indexPath.row == 0 {
vc.feed = "http://lapi.transitchicago.com/api/1.0/ttarrivals.aspx?key=mykey&mapid=40890&outputType=JSON"
}
if indexPath.row == 1 {
vc.feed = "http://lapi.transitchicago.com/api/1.0/ttarrivals.aspx?key=mykey&mapid=40820&outputType=JSON"
}
}
}

Answer 2

instead of
BlueBelmontTableViewController().feed = "http://lapi.transitchicago.com/api/1.0/ttarrivals.aspx?key=mykey&mapid=40890&outputType=JSON"
use
self.feed = "http://lapi.transitchicago.com/api/1.0/ttarrivals.aspx?key=mykey&mapid=40890&outputType=JSON"
beacause BlueBelmontTableViewController() is initialing new instance of BlueBelmontTableViewController and you want to change the instance you already have so you should use self instead of creating new instance.