👀 Views: 1411 💬 Answers: 1 📅 Created: 2025-06-27

swiftui list state-management Swift

I'm performance testing and I'm stuck on something that should probably be simple. I'm working with an scenario with maintaining the selection state in a SwiftUI List when the data is dynamically updated. I'm working on an iPhone 13 app where the user can select items from a list, but when the data is fetched from an API, the selection resets to the first item instead of preserving the current selection. Here's the relevant code snippet: ```swift struct ContentView: View { @State private var items: [String] = [] @State private var selectedItem: String? var body: some View { List(items, id: \.self, selection: $selectedItem) { item in Text(item) .onTapGesture { selectedItem = item } } .onAppear(perform: loadItems) } private func loadItems() { // Simulating an API call to fetch items DispatchQueue.main.asyncAfter(deadline: .now() + 1) { items = ["Item 1", "Item 2", "Item 3"] // Dynamic data } } } ``` The question arises when `loadItems()` fetches the data. The `selectedItem` is not correctly maintaining its state and is reset to `nil` when the items array is updated. I’ve tried using `@Binding` and `@ObservedObject` for managing the selection state, but those approaches didn’t work either. I also added a check to keep the `selectedItem` if it exists in the new items: ```swift if let currentSelection = selectedItem, items.contains(currentSelection) { // Preserve selection } ``` However, it seems the selection is lost because the List view is being rebuilt. I receive no behavior messages, but the selection behavior is not what I expect. Any insights on how to handle this situation without losing the selection state when the data updates would be greatly appreciated! My development environment is Ubuntu. Any help would be greatly appreciated! Any ideas what could be causing this? What are your experiences with this?