SwiftUI 在视图之间共享 model 数据

Question

I have such a structure, this structure seems wrong to me as the approach I want to ask you. So when I want to use 2 models in 1 view, I have to put it in foreach in one view. This is what I want. Using the data I use in my user's profile on other pages I want. How should I do this? How do you guys do it?

Let me give an example for your better understanding:

I want to show my user's Username data on the Homepage, how should I do this?. In fact, after initializing my model once, I want to use it in other views. What is the right approach.

  import SwiftUI

struct ContentView: View {
    @StateObject var network = ProfileNetwork()
    var body: some View {
        TabView{
            ProfileView().tabItem { Image(systemName: "house") }
            ForEach(self.network.userprofile,id:\.id){a in
                ShopView(profile_model: a)
            }.tabItem { Image(systemName: "house") }
        }
    }
}

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


class ProfileNetwork : ObservableObject {
    @Published var userprofile : [UserPRofile] = [UserPRofile(name: "Test", coin: 1, id: "dsa")]
}

struct ProfileView : View {
    @StateObject var network = ProfileNetwork()
    var body: some View {
        ForEach(self.network.userprofile, id:\.id){ i in
            ProfileViewModel(profile_model: i)
        }
    }
}

struct ProfileViewModel : View {
    var profile_model : UserPRofile
    var body: some View {
        Text(self.profile_model.name)
    }
}

struct UserPRofile : Decodable{
    var name : String
    var coin : Int
    var id : String
}

class ShopeNetwork : ObservableObject {
    @Published var shop : [ShopStore] = [ShopStore(id: "sda", image: "dasd", price: 100, name: "sda")]
}

struct ShopView : View {
    @StateObject var network = ShopeNetwork()
    var profile_model : UserPRofile
    var body: some View {
        ForEach(self.network.shop, id:\.id){ c in
            ShopViewModel(shop_model: c, profile_model: profile_model)
        }
    }
}

struct ShopViewModel : View {
    var shop_model : ShopStore
    var profile_model : UserPRofile
    var body: some View {
        Text(profile_model.name)
        Text(self.shop_model.name)
    }
}


struct ShopStore : Decodable {
    var id : String
    var image : String
    var price : Int
    var name : String
}

Answer 1

A possible solution is to create an @EnvironmentObject and inject it at the root level:

class AppState: ObservableObject {
    @Published var userProfile: UserPRofile?
}

@main
struct TestApp: App {
    @StateObject private var appState = AppState()

    var body: some Scene {
        WindowGroup {
            ContentView()
                .environmentObject(appState)
        }
    }
}

struct ProfileView: View {
    @EnvironmentObject private var appState: AppState // access as an `@EnvironmentObject`
    @StateObject var network = ProfileNetwork()
    var body: some View {
        VStack {
            ForEach(self.network.userprofile, id: \.id) { i in
                ProfileViewModel(profile_model: i)
            }
        }
        .onAppear {
            appState.userProfile = network.userprofile.first // set `userProfile` globally
        }
    }
}

struct ShopView: View {
    @EnvironmentObject private var appState: AppState // use it in any other view
    ...

Answer 2

Swift 5, iOS 14

Make the class a singleton so it becomes shareable easily.

class ProfileNetwork : ObservableObject {
    @Published var userprofile : [UserPRofile] = [UserPRofile(name: "Test", coin: 1, id: "dsa")]
    static var shared = ProfileNetwork()
}

And then refer to it with the shared handle.

struct ContentView: View {
  @StateObject var network = ProfileNetwork.shared
  var body: some View {

....
}

struct ProfileView : View {
  @StateObject var network = ProfileNetwork.shared 
  var body: some View {

....
}