Collection View Not Showing Data - ios

Question

My goal is to display data coming from a web service called News API into a collection view controller. Below is the data model and network manager.
struct News: Codable {
var status: String?
var totalResults: Int?
var articles: [Article]?
var article: Article?
enum CodingKeys: String, CodingKey {
case status = "status"
case totalResults = "totalResults"
case articles = "articles"
}
}
// MARK: - Article
struct Article: Codable {
var source: Source?
var author: String?
var title: String?
var articleDescription: String?
var url: String?
var urlToImage: String?
var publishedAt: String?
var content: String?
enum CodingKeys: String, CodingKey {
case source = "source"
case author = "author"
case title = "title"
case articleDescription = "description"
case url = "url"
case urlToImage = "urlToImage"
case publishedAt = "publishedAt"
case content = "content"
}
}
// MARK: - Source
struct Source: Codable {
var id: ID?
var name: Name?
enum CodingKeys: String, CodingKey {
case id = "id"
case name = "name"
}
}
enum ID: String, Codable {
case engadget = "engadget"
case techcrunch = "techcrunch"
case theVerge = "the-verge"
}
enum Name: String, Codable {
case engadget = "Engadget"
case lifehackerCOM = "Lifehacker.com"
case techCrunch = "TechCrunch"
case theVerge = "The Verge"
}
class NetworkManger{
static let shared = NetworkManger()
private let baseURL: String
private var apiKeyPathCompononent :String
private init(){
self.baseURL = "https://newsapi.org/v2/everything?q=NFT&sortBy=popularity&"
self.apiKeyPathCompononent = "apiKey=d32071cd286c4f6b9c689527fc195b03"
}
private var jsonDecoder:JSONDecoder = {
let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase
return decoder
}()
func getArticles() {
AF.request(self.baseURL + self.apiKeyPathCompononent, method: .get, parameters: nil, encoding: URLEncoding.default, headers: nil, interceptor: nil).response { (responseData) in
guard let data = responseData.data else {return}
do {
let news = try self.jsonDecoder.decode(News.self, from: data)
let nc = NotificationCenter.default
nc.post(name: Notification.Name("didFinishParsing"), object: nil)
} catch {
print(error)
}
}
}
}
It can display data from the web service to the console. The problem is that it can not show data to the collection view in NewsVC. I've done all necessary steps such as implementing the collection view data source, using an observer to alert the NewsVC that the JSON is parsed, setting the collection view layout, and registering the cell, but nothing seems to work. The code below is the NewVc and News grid; News Vc is meant to show the contents of the.
class NewsVC: UIViewController {
var news = [Article]()
#IBOutlet weak var collectionView: UICollectionView!
override func viewDidLoad() {
super.viewDidLoad()
configureCollection()
NetworkManger.shared.getArticles()
}
func configureCollection(){
collectionView.delegate = self
collectionView.dataSource = self
let collectionviewFlowLayout = UICollectionViewFlowLayout()
collectionviewFlowLayout.scrollDirection = .vertical
collectionviewFlowLayout.itemSize = CGSize(width: 188.0, height: 264.0)
collectionviewFlowLayout.minimumInteritemSpacing = 10.0
collectionView.collectionViewLayout = collectionviewFlowLayout
NotificationCenter.default.addObserver(self, selector: #selector(refreshcollectionView), name: Notification.Name("didFinishParsing"), object: nil)
}
#objc func refreshcollectionView(_ notification:Notification) {
guard let news = notification.object as? Article else { return}
print("News == \(news)")
self.news = [news]
print("Coount == \(self.news.count)")
DispatchQueue.main.async {
self.collectionView.reloadData()
}
}
extension NewsVC:UICollectionViewDataSource , UICollectionViewDelegate{
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
news.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "collectionCell", for: indexPath) as! NewsGridCell
let stories = news[indexPath.item]
cell.setCells(stories)
cell.backgroundColor = UIColor.red
return cell
}
class NewsGridCell: UICollectionViewCell {
#IBOutlet weak var newsImage: UIImageView!
#IBOutlet weak var newsDescription: UILabel!
#IBOutlet weak var author: UILabel!
func setCells(_ news:Article){
upDateUI(newDescription:news.articleDescription, author: news.author)
}
private func upDateUI(newDescription:String? , author:String?){
self.newsDescription.text = newDescription
self.author.text = author
}
}

Answer 1

Try instead of
nc.post(name: Notification.Name("didFinishParsing"), object: nil)
send
nc.post(name: Notification.Name("didFinishParsing"), object: news)
Then instead of
guard let news = notification.object as? Article else { return}
write
guard let news = notification.object as? News else { return}
print("News == \(news)")
self.news = news.articles

Answer 2

After reading the snippets, the code looks like it should works but it doesn't. In that case I would add debugPrint(#function) to check if following methods are executed:
NewsVC -> collectionView(_:numberOfItemsInSection:)
NewsVC -> collectionView(_:cellForItemAt:)
NewsGridCell -> setCells(_:)
If those debugPrints print to the console then I would go to the "View Hierarchy inspector" to examine presence and a view's sizes.