Creating a series of master detail lists from a single JSON file in SwiftUI

Question

I\'m trying to work through understanding how I can make data flow nicely through an app I\'m building. I just want a basic master detail view where it starts with a list of all

Answer 1

first you have to create CityListView and CityRow, like you did for users:

struct CityListView: View {
    var user: UserModel
    var body: some View {

            // don't forget to make CityModel Identifiable 
            List(user.cities) { city in
                CityRowView(city: city)
            }
            .navigationBarTitle(Text("Cities"))
        }
    }
}

struct CityRowView: View {
    var city: CityModel
    var body: some View {
        HStack {
            Text(city. name)
                .font(.headline)
            Spacer()
        }
    }
}

after that you need to change destination in NavigationLink (not UserRow, but new CityListView)

...
//NavigationLink(destination: UserRow(user: user)) {
NavigationLink(destination: CityListView(user: user)) {
    UserRow(user: user)
}
...

Another way is to declare variable "cities" as an array of CityModel and receive it from user:

struct CityListView: View {
    var cities: [UserModel]
    // list for array of cities
}

// in UserList
NavigationLink(destination: CityListView(cities: user.cities)) {
    UserRow(user: user)
}

P.S. Apple made excellent tutorial for navigations in SwiftUI: https://developer.apple.com/tutorials/swiftui/building-lists-and-navigation

Answer 2

Your CityModel and TownModel need to conform to Identifiable, just add an id to them like you did in UserModel.

Than you need to edit your UserList NavigationLink:

NavigationLink(destination: CityList(cities: user.cities)) {
    Text(user.firstName)
}

The Navigation is now like this: UserList -> CityList -> TownList

CityList:

struct CityList: View {

    var cities: [CityModel]

    var body: some View {
        List (cities) { city in
            NavigationLink(destination: TownList(towns: city.towns)) {
                Text(city.name)
            }
        }
    }
}

TownList:

struct TownList: View {

    var towns: [TownModel]

    var body: some View {
        List (towns) { town in
            Text(town.name)
        }
    }
}

I hope that helps, in my test project it works!