Alternative to switch statement in SwiftUI ViewBuilder block?

Question

⚠️ 23 June 2020 Edit: From Xcode 12, both switch and if let statements will be supported in the ViewBuilder!

I’ve been trying to replicate an app of

Answer 1

For not using AnyView(). I will use a bunch of if statements and implement the protocols Equatable and CustomStringConvertible in my Enum for retrieving my associated values:

var body: some View {
    ZStack {
        Color("background1")
            .edgesIgnoringSafeArea(.all)
            .onAppear { self.viewModel.send(event: .onAppear) }
        
        // You can use viewModel.state == .loading as well if your don't have 
        // associated values
        if viewModel.state.description == "loading" {
            LoadingContentView()
        } else if viewModel.state.description == "idle" {
            IdleContentView()
        } else if viewModel.state.description == "loaded" {
            LoadedContentView(list: viewModel.state.value as! [AnimeItem])
        } else if viewModel.state.description == "error" {
            ErrorContentView(error: viewModel.state.value as! Error)
        }
    }
}

And I will separate my views using a struct:

struct ErrorContentView: View {
    var error: Error

    var body: some View {
        VStack {
            Image("error")
                .resizable()
                .aspectRatio(contentMode: .fit)
                .frame(width: 100)
            Text(error.localizedDescription)
        }
    }
}