SwiftUI Calling NetworkModel from the View [closed] - swiftui

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I have been been reading a lot of about SwiftUI architecture. I read about MVVM, TCA, MVC etc. I am writing an app, where I have to get data from the JSON API and display it on the screen. I am following Apple's code samples and here is what I am doing.
For that I created a NetworkModel.
class NetworkModel {
func getPosts() async throws -> [Post] {
let (data, _) = try await URLSession.shared.data(from: URL(string: "https://jsonplaceholder.typicode.com/posts")!)
let posts = try JSONDecoder().decode([Post].self, from: data)
return posts
}
}
Post.swift
struct Post: Decodable {
let id: Int
let title: String
let body: String
}
PostListView
struct PostListView: View {
#State private var posts: [Post] = []
let networkModel = NetworkModel()
var body: some View {
List(posts, id: \.id) { post in
Text(post.title)
}.task {
do {
await networkModel.getPosts()
} catch {
print(error)
}
}
}
}
Everything works. Is this the right approach? I come from React background so in React if there is a component that is using state and that state will only be used for that component then we simply use private/local state.
I did not create any View Models etc for this app. Are VM's going to benefit me in someway?

Answer 1

The following example code is how I would approach using a NetworkModel.
Caveat, without dealing with the errors.
It creates a NetworkModel as a ObservableObject, which will make it easier
to update the data and have the UI refreshed automatically. The code uses
only one source of truth, the #StateObject var networkModel = NetworkModel(),
and nothing else. This, I believe is important for an architecture.
Is this the right approach?, well that is up to you to determine, by understanding
the various info you read, and your own experience.
struct Post: Decodable, Identifiable {
let userId: Int
let id: Int
let title: String
let body: String
}
#MainActor
class NetworkModel: ObservableObject {
#Published var posts: [Post] = []
func getPosts() async throws {
guard let url = URL(string: "https://jsonplaceholder.typicode.com/posts") else {return}
do {
let (data, _) = try await URLSession.shared.data(from: url)
self.posts = try JSONDecoder().decode([Post].self, from: data)
} catch {
print(error)
}
}
}
struct ContentView: View {
#StateObject var networkModel = NetworkModel()
var body: some View {
List (networkModel.posts) { post in
Text(post.title)
}
.task {
do {
try await networkModel.getPosts()
} catch {
print(error)
}
}
}
}
The info at the following link, gives some good explanations about how to manage data in your app and how SwiftUI has already a lot of structure/architecture built in to help you:
https://developer.apple.com/documentation/swiftui/managing-model-data-in-your-app

Answer 2

SwiftUI is an architecture in itself, it's best to just learn it. E.g. learn the View struct, learn how body func is called if a let property or an #State or #Binding changes. It's really quite simple.