Failed to update SwiftUI preview when using .OnReceive Method

Question

I have implemented the .OnReceive method in a SwiftUI view to be able to keep track of some variebles.

But as you can see I have all the .onReceive's code is commented and the reason is that if I don't I get the following error on the canvas:

This is my ContentView_Previews Struct:

Could anyone help me to understand the error? I suspect that the ContentView_Previews Struct need some extra value to be able to interpret the view on the canvas.

Thanks for the help!

Answer 1

This error means that the preview cannot render, and the reason for that is that it doesn't have the @EnvironmentObject var appState: States that your LoginView uses in the .onReceive .

So, you need to set it:

struct ContentView_Previews: PreviewProvider {
   static var previews: some View {
      LoginView()
         .previewLayout(.device)
         .environmentObject(States())  // here
   }
}