SwiftUI MVVM with Networking

It can’t be that hard!

Photo by Maxwell Nelson on Unsplash

Difficulty: Beginner | Easy | Normal | Challenging

This article has been developed using Xcode 12.1, and Swift 5.3

If you want to develop any sort of `SwiftUI` application you

Prerequisites:

• You will be expected to make a Single View SwiftUI Application in Swift.

Terminology

SwiftUI: A simple way to build user interfaces Across Apple platforms

The motivation

You will need to create nicely featured Apps. They are going to (probably) make network calls. This means that you need to develop an architecture that is going to support this in your development.

Let’s go MVVM!

The basic architecture

The Main view (which I’ve creatively called ContentView) is instantiated with a view model which is creatively called ContentViewModel.

Therefore in the SceneDelegate contentView is created with let contentView = ContentView(viewModel: ContentViewModel()).

My ContentView isn’t going to do anything in this case, apart from creating a reference to the view model

struct ContentView: View {
    @ObservedObject var viewModel: ContentViewModel
    
    init(viewModel: ContentViewModel) {
        self.viewModel = viewModel
    }
    
    var body: some View {
        NavigationView {
            List {
                ForEach(viewModel.users, id: \.self) {
                    user in
                    
                    Text("\(user.title)")
                }
            }
            .navigationBarTitle("User")
            .listStyle(GroupedListStyle())
        }
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView(viewModel: ContentViewModel())
    }
}

We are going to have the following view model

class ContentViewModel: ObservableObject {
    @Published var users: [User] = []
    var res: AnyCancellable?
    private var networkManager: AnyNetworkManager<URLSession>?
    
    init() {
        self.networkManager = AnyNetworkManager(manager…