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CoreData and Preview (accessing a UUID property in the preview container)

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I am not sure whether this questions belongs to the Swift or SwuiftUI thread but here it is: I define a couple of dummy entities in my preview container, and in some Views, I fetch them using an "id" predicate. How do I make this preview work, ie, how can I access the assigned UUID in my preview entities?

recipe_id would be one of the dummy recipes' id created in the Persistence class.

Basically it would be something like:

struct DetailedRecipeView_Previews: PreviewProvider {

    static var previews: some View {

        return DetailedRecipeView(for: recipe_id).environment(\.managedObjectContext, PersistenceController.preview.container.viewContext)

The view itself is initialized like that:

    @FetchRequest private var recipe: FetchedResults<Recipe>

    init(for id: UUID) {
        _recipe = FetchRequest(
            entity: Recipe.entity(),
            sortDescriptors: [NSSortDescriptor(keyPath: \, ascending: true)],
            predicate: NSPredicate(format: "recipe_id == %@", id as CVarArg),
            animation: .default)

The preview is working well when starting from the Root view and going down.

Thanks Alessandro


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