How to pass API data to table view cells - ios

Question

I'm having some trouble passing my API returned data to table view cells. I am appending the data to an array and then passing this array to the table view (as usual) to get the number of rows and data for the cells. When I print inside the function where I am appending, the titles are shown in the array. Outside they're not. Any idea? Relevant code below:
class ProductTableViewController: UITableViewController, UISearchBarDelegate {
#IBOutlet weak var searchBar: UISearchBar!
#IBOutlet var tabView: UITableView!
var filteredData = ["Title1"]
override func viewDidLoad() {
super.viewDidLoad()
getProducts { (products) in
for product in products {
self.filteredData.append(product.title)
}
}
}
func getProducts(completionHandler: #escaping([ProductDetail]) -> Void) {
let url = URL(string: "exampleAPIURL")!
let dataTask = URLSession.shared.dataTask(with: url) {data, _, _ in
guard let jsonData = data else { return }
do {
let decoder = JSONDecoder()
let productsResponse = try decoder.decode(Products.self, from: jsonData)
let productDetails = productsResponse.data
for name in productDetails {
self.filteredData.append(name.title)
}
completionHandler(productDetails)
}catch {
print(error.localizedDescription)
}
}
dataTask.resume()
}
override func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
if filteredData == nil {
return 1 }
else {
return filteredData.count
}
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) ->
UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as UITableViewCell
for name in filteredData {
if name != nil {
let product = filteredData[indexPath.row]
cell.textLabel?.text = product
} else {
cell.textLabel?.text = "name"
}
}
return cell
}
I am only receiving the hardcoded strings in the filteredData array when I run the simulator. Is there a different way to pass the JSON?
Many thanks!

Answer 1

Reload the table view after the data is collected:
getProducts { (products) in
for product in products {
self.filteredData.append(product.title)
}
self.tabView.reloadData()
}

Answer 2

After setting the array, you need to call self.tableView.reloadData() and invoke it on the main thread.
Also, its better to do the products API call from viewDidAppear as if the API call from viewDidLoad returns fast enough, operations on the view might fail. Also you might want to show some activity indicator.
override func viewDidAppear() {
super.viewDidLoad()
getProducts { (products) in
for product in products {
self.filteredData.append(product.title)
}
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
}