Display information from decoded JSON in a UILabel (Swift 4) - ios

Question

I am trying to display information taken from JSON. I've used .decode to get it. Now I want to put its text onto a simple label on my storyboard. At the bottom under ".resume()" is my attempt and it isn't working. I can't seem to figure this out.
import UIKit
struct WebsiteDescription: Decodable {
var name : String
var description : String
var courses : [Course]
}
struct Course: Decodable {
let id: Int
let name: String
let link: String
let imageUrl: String
}
class ViewController: UIViewController {
#IBOutlet weak var displayLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
let jsonUrlString = "https://api.letsbuildthatapp.com/jsondecodable/website_description"
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 websiteDescription = try JSONDecoder().decode(WebsiteDescription.self, from: data)
print(websiteDescription.name, websiteDescription.description, websiteDescription.courses)
//let courses = try JSONDecoder().decode([Course].self, from: data)
} catch let jsonErr {
print("Error serializing json", jsonErr)
}
}.resume()
let displayLabel.text = websiteDescription.name
}
}

Answer 1

You need to update your label from within the do method. Also you should do it from the main thread so that the UI can be updated. I have updated the code below.
import UIKit
struct WebsiteDescription: Decodable {
var name : String
var description : String
var courses : [Course]
}
struct Course: Decodable {
let id: Int
let name: String
let link: String
let imageUrl: String
}
class ViewController: UIViewController {
#IBOutlet weak var displayLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
let jsonUrlString = "https://api.letsbuildthatapp.com/jsondecodable/website_description"
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 websiteDescription = try JSONDecoder().decode(WebsiteDescription.self, from: data)
print(websiteDescription.name, websiteDescription.description, websiteDescription.courses)
//let courses = try JSONDecoder().decode([Course].self, from: data)
DispatchQueue.main.async {
self.displayLabel.text = websiteDescription.name
}
} catch let jsonErr {
print("Error serializing json", jsonErr)
}
}.resume()
}