How can I create a horizontal TextField with a "done" button to dismiss it in SwiftUI?

I have text fields in my app that need to have a vertical axis (multi-lined) so the use can enter long textual inputs and easily see what they're doing. I would like to have a done button that lets them dismiss the onscreen keyboard or better yet, jump to the next field if there is one. I would really love a pure SwiftUI solution

I have tried

Using .submitLabel(.done), this creates the done button but it adds a new line when pressed, rather than dismissing the keyboard.
Using the onCommit argument of TextField and passing in a function that dismisses the keyboard. This works but you can't use both the onCommit and axis arguments on a given TextField
Setting .lineLimit(nil), had no effect
Wrapping the textView in an HStack, which of couse had no effect

Solution

You can control the focus of a textfield (wether if it is active or not) with the @FocusState wrapper in combination with the .focused(_) modifier, like so:

import SwiftUI

struct ContentView: View {
    
    // @FocusState can change the focus of a textfield (if it is active or not)
    @FocusState var isEmail: Bool  
    @FocusState var isUsername: Bool  
    @FocusState var isPassword: Bool  
    
    @State var email: String = ""
    @State var username: String = ""
    @State var password: String = ""
    
    var body: some View {
        VStack {
            TextField("Email", text: $email, axis: .horizontal)
                .submitLabel(.continue)
                .focused($isEmail) // connects the `isEmail` focus state value to the email textfield 
                .onSubmit() {
                    // on submit, when the user hits enter, the email focus gets removed and the username focus gets activated
                    isEmail = false
                    isUsername = true
                }
            
            TextField("Username", text: $username, axis: .horizontal)
                .submitLabel(.continue)
                .focused($isUsername)
                .onSubmit() {
                    isUsername = false
                    isPassword = true
                }
            
            SecureField("Password", text: $password)
                .submitLabel(.done)
                .focused($isPassword)
                .onSubmit() {
                    isPassword = false 
                }
        }
        .textFieldStyle(.roundedBorder)
        .padding()
        .onAppear {
            isEmail = true // default focus when the view appears is the mail textfield
        }
    }
}