saoudrizwan

import UIKit

class ControllerView: UIView {
    
    weak var controller: Controller?
    
    init(controller: Controller) {
        super.init(frame: controller.view.frame)
        controller.view.addSubview(self)
        self.translatesAutoresizingMaskIntoConstraints = false

saoudrizwan

class MainController: Controller {
    
    var mainControllerView: MainControllerView {
        get {
            guard let controllerView = self.controllerView as? MainControllerView else { fatalError("Controller view has not been set") }
            return controllerView
        }
    }
    
    override func viewDidLoad() {

saoudrizwan

enum Result<Value> {
    case success(Value)
    case failure(Error)
}

func getPosts(for userId: Int, completion: ((Result<[Post]>) -> Void)?) {
    var urlComponents = URLComponents()
    urlComponents.scheme = "https"
    urlComponents.host = "jsonplaceholder.typicode.com"
    urlComponents.path = "/posts"

saoudrizwan

struct Post: Codable {
    let userId: Int
    let id: Int
    let title: String
    let body: String
}

saoudrizwan

{
  "userId": 1,
  "id": 1,
  "title": "sunt aut facere repellat provident occaecati excepturi optio reprehenderit",
  "body": "quia et suscipit\nsuscipit recusandae consequuntur expedita et cum\nreprehenderit molestiae ut ut quas totam\nnostrum rerum est autem sunt rem eveniet architecto"
}

saoudrizwan

struct Post: Codable {
    let user: Int
    let body: String
    
    enum CodingKeys: String, CodingKey {
        case user = "userId"
        case body
    }
}

saoudrizwan

var posts = [Post]()

func buttonTapped() {
    getPosts(for: 1) { (result) in
        switch result {
        case .success(let posts):
            self.posts = posts
        case .failure(let error):
            fatalError("error: \(error.localizedDescription)")
        }

saoudrizwan

// Helper method to get a URL to the user's documents directory
// see https://developer.apple.com/icloud/documentation/data-storage/index.html
func getDocumentsURL() -> URL {
    if let url = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first {
        return url
    } else {
        fatalError("Could not retrieve documents directory")
    }
}

saoudrizwan

let myPost = Post(userId: 1, id: 1, title: "Hello World", body: "How are you all today?")

func submitPost(post: Post) {
    // ... 
}

saoudrizwan

// We'll need a completion block that returns an error if we run into any problems
func submitPost(post: Post, completion:((Error?) -> Void)?) {
    var urlComponents = URLComponents()
    urlComponents.scheme = "https"
    urlComponents.host = "jsonplaceholder.typicode.com"
    urlComponents.path = "/posts"
    guard let url = urlComponents.url else { fatalError("Could not create URL from components") }
    
    // Specify this request as being a POST method
    var request = URLRequest(url: url)