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Unexpected Crash When Using SwiftUI's NavigationView with Dynamic Data in iOS 17

πŸ‘€ Views: 219 πŸ’¬ Answers: 1 πŸ“… Created: 2025-06-09
swift swiftui navigation

I'm confused about Hey everyone, I'm running into an issue that's driving me crazy. I'm working with an scenario with my SwiftUI application where using `NavigationView` with dynamic data causes the app to crash unexpectedly. My app lists items fetched from an API, and I've wrapped this in a `NavigationView`. The crash occurs when navigating to a detail view of an item. Here’s a simplified version of my code: ```swift import SwiftUI struct Item: Identifiable { var id: String var title: String } struct ContentView: View { @State private var items: [Item] = [] var body: some View { NavigationView { List(items) { item in NavigationLink(destination: DetailView(item: item)) { Text(item.title) } } .navigationTitle("Items") } .onAppear { fetchItems() } } private func fetchItems() { // Simulating API call DispatchQueue.main.asyncAfter(deadline: .now() + 1) { self.items = [ Item(id: "1", title: "Item 1"), Item(id: "2", title: "Item 2"), Item(id: "3", title: "Item 3") ] } } } struct DetailView: View { var item: Item var body: some View { Text(item.title) .navigationBarTitle(item.title, displayMode: .inline) } } ``` When I run the app, the initial list displays correctly, but if I tap on any item, I get the following behavior in the console: ``` Fatal behavior: Index out of range ``` I've tried wrapping the `NavigationLink` in a `Group` and ensuring that the `items` array is populated properly before navigation occurs, but it still fails. I'm also using Xcode 15.0 and testing on an iPhone 14 Pro running iOS 17. Is there something I might be overlooking regarding state management or potential threading issues? Any help would be greatly appreciated! This is part of a larger service I'm building. This is part of a larger CLI tool I'm building.