Problems with EnvironmentObject in ModalView

Question

I have created a simple List and want to add users to it. My project has CoreDate activated and I have add the following Code to the SceneDelegate:

    let userStorage = UserStorage()
    let contentView = ContentView().environment(\.managedObjectContext, context).environmentObject(userStorage)

The code of the ContentView is this:

import SwiftUI

struct User: Identifiable {
    var id = UUID()
    var firstName = ""
    var lastName = ""
}

class UserStorage: ObservableObject {
    @Published var users = [User]()
}

struct ContentView: View {

    @State private var presentation = false
    @EnvironmentObject var userStorage: UserStorage

    var body: some View {

        VStack {
            Button(action: {
                self.presentation = true
            }) {
                Text("New User")
            }.sheet(isPresented: $presentation, onDismiss: {
                self.presentation = false
            }) {
                newuserView(presentation: self.$presentation, newUser: User())
            }
            List(userStorage.users) { singleUser in
                VStack {
                    Text(singleUser.firstName)
                    Text(singleUser.lastName)
                }
            }
        }
    }
}

struct newuserView : View {
    @Binding var presentation: Bool
    @State var newUser: User
    @EnvironmentObject var userStarage: UserStorage

    var body: some View {
        VStack {
            TextField("Put in first name please", text:$newUser.firstName)

            TextField("Put in last name please", text:$newUser.lastName)

            Button(action: {
                self.userStarage.users.append(self.newUser)
                self.presentation = false
            }) {
                Text("Add new User")
            }disabled(newUser.lastName.isEmpty || newUser.firstName.isEmpty)
        }.padding(.horizontal)
    }
}
struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

When I run my project and want to add a user, I get the following error:

Thread 1: Fatal error: No ObservableObject of type UserStorage found. A View.environmentObject(_:) for UserStorage may be missing as an ancestor of this view.

I have tried to do this with .sheet, but it doesn't work

score 1 · Answer 1 · answered Jan 11 '20 at 09:12

Sheet creates different view hierarchy so .environmentObject is not injected in view to be shown in sheet by default - you have to do it manually

}.sheet(isPresented: $presentation, onDismiss: {
    self.presentation = false
}) {
    newuserView(presentation: self.$presentation, newUser: User())
        .environmentObject(self.userStorage)
}

Problems with EnvironmentObject in ModalView

1 Answers1