Hello everyone!

So I've created a new structure called OrderModel

struct OrderModel: Codable {
    var type: Int
    var quantity: Int

    var extraFrosting = false
    var addSprinkles = false

    var name: String
    var streetAddress: String
    var city: String
    var zip: String

    var specialRequestEnabled = false {  ...  } 
    var cost:  Double { ... }

    static let types = ["Vanilla", "Strawberry", "Chocolate", "Rainbow"]
}

This is what my class looks like:

class OrderViewModel: ObservableObject, Codable {

    @Published var order = OrderModel() // Missing argument for parameter 'from' in call 

    enum CodingKeys: CodingKey {
        case order
    }

    func encode(to encoder: Encoder) throws {
        var containter = encoder.container(keyedBy: CodingKeys.self)
        try containter.encode(order, forKey: .order)

    }

    required init(from decoder: Decoder) throws {
        let containter = try decoder.container(keyedBy: CodingKeys.self)
        order = try containter.decode(order.self, forKey: .order)

    }

    init() {}
}

I do not really know how to display this data now..

struct CupCake: View {
    @StateObject var vm = OrderViewModel()

    var body: some View {
        NavigationView {
            Form {
                Section {
                    Picker("Select your cake type", selection: $vm.order.type ) {
                        ForEach(OrderModel.type.indices) {
                            Text(OrderViewModel.types[$0])
                        }
                    }

                    Stepper("Number of cakes: \(order.quantity)", value: $order.quantity, in: 3...20)
                }

I have tried with :

Picker("Select your cake type", selection: $vm.order.type ) { ... }
Picker("Select your cake type", selection: $OrdelModel.type ) { ... } 

@TooMaa is scratching his head....

I do not really know how to display this data now.

I like to think of ForEach as a view factory!
See -> View Factory
or See -> View Factory
or See -> View Factory

So, ask yourself: What is my ForEach view factory trying to make?

ForEach(OrderModel.type.indices) {
    Text(OrderViewModel.types[$0])  // <-- What is the ForEach view factory trying to make?
}

Answer: Your view factory is trying to make a Text view for each type in your OrderModel.

WAIT WHUT???!?!?

Each type in your what?

Please examine your OrderModel closely. Have you defined "type" in your OrderModel?

Also note: type is probably a very bad name to use because of its definition within the Swift language. Instead, be more verbose to capture the nature of this variable. Perhaps cupcakeType might be a better (less confusing?) name!

Keep coding. Please let us know how you solved this.