update View when view model's, publish object's, property is updated - swiftui

Question

How to update view, when view models publish var's (user's) , name property is updated. I do know why its happening but what is the best way to update the view in this case.
class User {
var id = "123"
#Published var name = "jhon"
}
class ViewModel : ObservableObject {
#Published var user : User = User()
}
struct ContentView: View {
#ObservedObject var viewModel = ViewModel()
var body: some View {
userNameView
}
var userNameView: some View {
Text(viewModel.user.name)
.background(Color.red)
.onTapGesture {
viewModel.user.name += "update"
print( viewModel.user.name)
}
}
}
so one way i do it, is by using onReceive like this,
var body: some View {
userNameView
.onReceive(viewModel.user.$name){ output in
let tmp = viewModel.user
viewModel.user = tmp
print("onTapGesture",output)
}
}
but it is not a good approach it will update all view using users properties.
should i make a #state var for the name?
or should i just make a ObservedObject for user as well?

Answer 1

Make you class conform to ObservableObject
class User: ObservableObject {
var id = "123"
#Published var name = "jhon"
}
But he catch with that is that you have to observe it directly you can't chain it in a ViewModel
Use #ObservedObject var user: User in a View

Answer 2

You should use struct:
import SwiftUI
struct User {
var id: String
var name: String
}
class ViewModel : ObservableObject {
#Published var user : User = User(id: "123", name: "Mike")
}
struct ContentView: View {
#ObservedObject var viewModel: ViewModel = ViewModel()
var body: some View {
userNameView
}
var userNameView: some View {
Text(viewModel.user.name)
.background(Color.red)
.onTapGesture {
viewModel.user.name += " update"
print( viewModel.user.name)
}
}
}