Pass API data when tap on CollectionVC to TableVC - ios

Question

I'm trying to pass data from a news Api to a tableView, but I'm having an issue, the data is returning nil when it get's pass to the SectorNewsVC, And by the time it gets to the infoVC it's still nil, however when I print the data before it gets pass it there. Can someone explain what I am doing wrong and, how I can go about fixing it? Thank You!!
This is where I'm creating the URLSession and fetching the data, and attempting to pass the data over to the Viewcontroller which is calling the fetchSectorNews() to retrive the data from an API.
struct FetchCategoryResponse {
let sectorUrl = "https://stocknewsapi.com/api/v1/category?section=alltickers&items=50&type=article&token=\(Key.api_key)"
func fetchSectorNews(sector: String) {
let urlString = "\(sectorUrl)&sector=\(sector)"
performRequest(urlString: urlString)
print(urlString)
}
func performRequest(urlString: String) {
// create url
if let url = URL(string: urlString) {
// create url session
let session = URLSession(configuration: .default)
// give session a task
let task = session.dataTask(with: url) { (data, response, error) in
if error != nil {
print(error!)
return
}
if let safeData = data {
if let news = self.parseJson(sectorData: safeData) {
DispatchQueue.main.async {
let vc = SectorNewsVC()
vc.dataToPass = news
}
}
}
}
task.resume()
}
}
// parse the jason data
func parseJson(sectorData: Data) -> SectorModel? {
let decoder = JSONDecoder()
do {
let decodedData = try decoder.decode(CatergoryData.self, from: sectorData)
let newsUrl = decodedData.data[1].title
let imageUrl = decodedData.data[1].news_url
let title = decodedData.data[1].title
let source = decodedData.data[1].source_name
let sectorPayload = SectorModel(url: newsUrl, image: imageUrl, title: title, source: source)
// this sectorpayload gets saved to the news var in the performrequest() bc its being return
return sectorPayload
}
catch {
print(error)
return nil
}
}
} // END Struct
so in this ViewController I'm setting up the collectionViewController and calling the fetchSectorNews() and passing in the title of the label as the argunemt for the function, while trying to pass the data over to the detialViewController
var titleArr = ["Technology", "Materials", "HealthCare"]
var dataToPass: SectorModel?
var fetchNews = FetchCategoryResponse()
extension SectorNewsVC: UICollectionViewDelegate, UICollectionViewDataSource {
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return titleArr.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "cellId", for: indexPath) as! SectorCollectionCell
cell.listLabel.text = titleArr[indexPath.row]
return cell
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
let curentIndex = indexPath.item
if curentIndex == 0 {
fetchNews.fetchSectorNews(sector: "technology")
}
else if curentIndex == 1 {
fetchNews.fetchSectorNews(sector: "materials")
}
else if curentIndex == 2 {
fetchNews.fetchSectorNews(sector: "healthcare")
}
performSegue(withIdentifier: "segue", sender: nil)
} // end cv()
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "segue" {
if let indexPath = self.collectionView.indexPathsForSelectedItems {
let detailVC = segue.destination as! infoVC
detailVC.newData = dataToPass
print(indexPath)
}
}
}
}
Here is where I want to display the data
class infoVC: UIViewController, UITableViewDelegate, UITableViewDataSource {
#IBOutlet weak var tableView: UITableView!
var newData: SectorModel?
override func viewDidLoad() {
super.viewDidLoad()
tableView.delegate = self
tableView.dataSource = self
tableView.separatorStyle = .none
tableView.showsVerticalScrollIndicator = false
tableView.backgroundColor = #colorLiteral(red: 0.1926331222, green: 0.2233074605, blue: 0.3540094197, alpha: 1)
tableView.register(UINib(nibName: "DifferentSectorCell", bundle: nil), forCellReuseIdentifier: "cellId")
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 100
}
func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
cell.backgroundColor = UIColor.clear
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 5
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
print("tap")
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cellId", for: indexPath) as! DifferentSectorCell
cell.titleLabel.text = "hey"
cell.sourceLabel.text = "hello"
return cell
}
}

Answer 1

I would suggest a different approach. Sending the section to the child controller, and do the request on the child. Here is what has worked for me before
on the parent controller:
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
let curentIndex = indexPath.item
var sector = ""
if curentIndex == 0 {
sector = "technology"
}
else if curentIndex == 1 {
sector = "materials"
}
else if curentIndex == 2 {
sector = "healthcare"
}
performSegue(withIdentifier: "segue", sender: sector)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "segue" {
let detailVC = segue.destination as! infoVC
detailVC.sector = sender as! String
}
}
}
on the child controller:
var sector = ""
override func viewWillAppear() {
super.viewWillAppear()
fetchNews.fetchSectorNews(sector: self.sector)
}