How to add UIActivityIndicatorView by using URLSession in Swift? - ios

Question

I have the Master-Detail project where I am parsing data from JSON. The purpose is to add UIActivityIndicatorView (by using URLSession) to the DetailsViewController while waiting for data be fetched and loaded to the DetailsViewController. I have tried several ways by starting UIActivityIndicatorView in Master after the following:
let task = URLSession.shared.dataTask(with: url!) { (data, response, error) in
Also I do not know where to stop it, I have tried it in ViewDidLoad() of the DetailViewController (before configureView()):
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
configureView()
}
But also did not work. I could not find anywhere the information about adding activity indicator by using the state of URLSession. Here I add the code from MasterViewController where I have tried to start the activity indicator:
let arrayOfUrls = [ URL(string: "http://www.omdbapi.com/?t=The+Dark+Knight&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=The+Lord+of+the+Rings%3A+The+Return+of+the+King&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=Forrest+Gump&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=Inception&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=The+Matrix&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=Interstellar&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=The+Pianist&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=The+Intouchables&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=The+Departed&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=The+Prestige&apikey=f85dc75e") ]
for url in arrayOfUrls {
let task = URLSession.shared.dataTask(with: url!) { (data, response, error) in
if let error = error {
print (error)
} else {
if let data = data {
do {
let movie = try JSONDecoder().decode(Movie.self, from: data)
print(movie.Title)
self.objects.append(movie.Title)
self.details.append(movie)
} catch {
print("Json Processing Failed")
}
}
}
}
task.resume()
}
}

Answer 1

Create NetworkService class and do api calls in a func, this way much better.
class NetworkService {
let arrayOfUrls = [ URL(string: "http://www.omdbapi.com/?t=The+Dark+Knight&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=The+Lord+of+the+Rings%3A+The+Return+of+the+King&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=Forrest+Gump&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=Inception&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=The+Matrix&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=Interstellar&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=The+Pianist&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=The+Intouchables&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=The+Departed&apikey=f85dc75e"), URL(string: "http://www.omdbapi.com/?t=The+Prestige&apikey=f85dc75e") ]
func getData(completion:#escaping(Movie)->()){
for url in arrayOfUrls {
let task = URLSession.shared.dataTask(with: url!) { (data, response, error) in
var movie = Movie()
if let error = error {
print (error)
} else {
if let data = data {
do {
movie = try JSONDecoder().decode(Movie.self, from: data)
print(movie.Title)
self.objects.append(movie.Title)
self.details.append(movie)
} catch {
print("Json Processing Failed")
}
}
}
completion(movie)
}
task.resume()
}
}
}
In view Controller call your func:
let networkService = NetworkService()
activityIndicator.startAnimating()
networkService.getData { result in
self.activityIndicator.stopAnimating()
//result your movie data do whatever yo want it
DispatchQueue.main.async {
//If you need to reload tableview or etc. do here
}
}