How to populate TableViewCell with JSON data using Codable protocol in Swift4? - tableview

Question

Solved
I am trying to populate Table View Cell from sample JSON in this link https://api.myjson.com/bins/13axs1, but getting error in cellForRowAt function when trying to assign textLabel.
type '[City]?' has no subscript members
JSON
[
{
"name": "New York",
"information": "Later will be added",
"imageUrl": "later"
},
{
"name": "New York",
"information": "Later will be added",
"imageUrl": "later"
}
]
The code in ViewController:
struct City: Codable {
let name: String?
let information: String?
let imageUrl: String?
}
class ViewController: UIViewController {
#IBOutlet weak var tableView: UITableView!
var citiesList: [City] = []
override func viewDidLoad() {
super.viewDidLoad()
let jsonUrlString = "https://api.myjson.com/bins/13axs1"
guard let url = URL(string: jsonUrlString) else { return }
URLSession.shared.dataTask(with: url) { (data, response, err) in
guard let data = data else { return }
do {
let cities = try JSONDecoder().decode([City].self, from: data)
if cities != nil{
self.citiesList = cities
}else {
print("nothing to display")
}
DispatchQueue.main.async {
self.tableView.reloadData()
}
} catch let jsonErr {
print("Error serializing json:", jsonErr)
}
}.resume()
}
}
extension ViewController: UITableViewDataSource {
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return citiesList.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = UITableViewCell()
cell.textLabel?.text = citiesList[indexPath.row].name // here I am getting error type '[City]? has no subscript members
return cell
}
}
Sorry, but I don't know why not all of the code shows clearly after I added it, but hope it will be clear for you guys to understand, thanks a lot.

Answer 1

You are missing the reload method (reloadData()):
URLSession.shared.dataTask(with: url) { (data, response, err) in
guard let data = data else { return }
do {
let cities = try JSONDecoder().decode([City].self, from: data)
self.citiesList = cities
DispatchQueue.main.async {
self.tableView.reloadData()
}
} catch {
print("Error serializing json:", error)
}
}.resume()
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.deque...
cell.textLabel?.text = citiesList?[indexPath.row].name
return cell
}