App Crashes After Second API Call (Swift) - ios

Question

I'm trying to fetch data from an API through an HTTP get method in Swift 5. It successfully loads the data on launch, but when I refresh the page it says the "index is out of range", this is because the data is no longer be fetched in my logged, hence there is nothing in the index. Is this a common issue or does this just pertain to me? I've attached my code below and have highlighted where the error shows up. Thank you!
import UIKit
import Foundation
class TheClass: UIViewController, UITableViewDataSource, UITableViewDelegate {
#IBOutlet weak var pageView: UITableView!
struct StocksObject {
var volume: String?
}
struct Response: Codable {
let _type: String?
let readLink: String?
let totalEstimatedMatches: Int?
let value: [Value]?
}
struct QueryContext: Codable {
let originalQuery: String?
let adultIntent: Bool?
}
struct Value: Codable {
let name: String?
}
var stocks_object = [StocksObject]()
var news_object = [Value]()
override func viewDidAppear(_ animated: Bool) {
self.news_object.removeAll()
self.getNews()
}
override func viewDidLoad() {
super.viewDidLoad()
getData()
getNews()
pageView.delegate = self
pageView.dataSource = self
}
func getNews() {
let request = NSMutableURLRequest(url: NSURL(string: "https://example.com")! as URL,
cachePolicy: .useProtocolCachePolicy,
timeoutInterval: 10.0)
request.httpMethod = "GET"
request.allHTTPHeaderFields = headers
URLSession.shared.dataTask(with: request as URLRequest) { (data, response, error) in
guard let data = data else { return }
do {
let obj: Response = try JSONDecoder().decode(Response.self, from: data)
let json = try JSONSerialization.jsonObject(with: data, options: [])
print(json)
let objectReview = Value(name: obj.value?[0].name)
self.news_object.append(objectReview)
print("\(String(describing: obj.value?[0].name))")
print("\(String(describing: obj.value?[2].name))")
} catch {
print("ERROR: \(error)")
self.performSegue(withIdentifier: "InvalidSymbol", sender: nil)
}
}.resume()
}
func getData() {
let url = URL(string: "https://example2.com")!
var request = URLRequest(url: url)
request.httpMethod = "GET"
NSURLConnection.sendAsynchronousRequest(request, queue: OperationQueue.main) {
(response, data, error) in
if let data = data {
do {
let json = try JSONDecoder().decode(Root.self,from: data)
let Volume = json.data.first?.volume
struct Root: Codable {
let data: [Datum]
}
struct Datum: Codable {
let volume: String
}
print(json)
let object = StocksObject(volume: Volume)
self.stocks_object.append(object)
DispatchQueue.main.async {
self.pageView.reloadData()
}
} catch {
print(error)
}
}
}
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 825
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return stocks_object.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell") as! StockCell
let object = stocks_object[indexPath.row]
//Error is coming in here:
let objectNews = news_object[indexPath.row]
cell.volume.text = object.volume
cell.newsOne.text = objectNews.name
return cell
}
}

Answer 1

Inside viewDidAppear, you need to empty your "news_object" Array when page loads and then call self.getNews() inside viewDidAppear.
Inside viewDidAppear:
self.news_object.removeAll()
self.getNews()
Since you edited your question so here is the reason why you are facing this error.
For above code you need to create switch statement that check which array.count to return and do same in cellForRowAt. Because they both have different length that's the reason you are facing error "Out of Range"
I hope its clear now.