I have a Category model that's defined like so:
@Model
final class Category {
@Attribute(.unique) var id: UUID
var name: String
var parent_id: UUID? //categories can be children of other categories
init(id: UUID, name: String, parent_id: UUID?) {
self.id = id
self.name = name
self.parent_id = parent_id
}
}
And I'm getting my categories from an API call and putting it into my View:
import SwiftUI
import SwiftData
struct CategoryView: View {
@Environment(\.modelContext) private var modelContext
@Query private var categories: [Category]
@Query(filter: #Predicate<Category>{ $0.parent_id == nil })
private var top_level_categories: [Category]
var spacing: CGFloat = 25
var body: some View {
HStack() {
Text("Categories")
.font(.title.bold())
Spacer()
Text("see all")
}
.padding([.bottom, .top], 0)
VStack(spacing: 20) {
ScrollView(.horizontal) {
HStack(spacing: spacing) {
ForEach(top_level_categories) { category in
Text(category.name!)
}
}
}
}
.onAppear{
getCategories()
}
}
func getCategories() {
get_refresh_token { token in
guard let token = token else {
return
}
var urlRequest = URLRequest (url: URL(string:"https://api.test.com/categories")!)
urlRequest.httpMethod = "GET"
urlRequest.addValue("application/json", forHTTPHeaderField: "Content-Type")
urlRequest.addValue("Bearer \(token)", forHTTPHeaderField: "Authorization")
URLSession.shared
.dataTask(with: urlRequest) { (data, response, error) in
do {
if let data = data {
let c = try JSONDecoder().decode([Category].self, from: data)
c.forEach { modelContext.insert($0) }
try? modelContext.save()
}
}
catch {
print(error)
}
}.resume()
}
}
}
This runs fine the first time I run the app but when I run it again, I get the following error:
ForEach<Array<Category>, UUID, Text>: the ID XXXXXX-XXXX-XXXX-XXXX-XXXXXX occurs multiple times within the collection, this will give undefined results!
Not sure why this is happening since I thought putting the @Attribute(.unique) on ID means that the same category won't get added twice?
