Hi @b_rare, your message helped knock my brain into gear when I was really confused, thank you... in case this helps you or any other lost devs...
I was seeing this same Task or actor isolated value cannot be sent warning on Xcode 16.1 when I tried to do something very similar:
Unable to move from nonisolated to @MainActor with a Task
extension ViewController: MKLocalSearchCompleterDelegate {
nonisolated func completerDidUpdateResults(_ completer: MKLocalSearchCompleter) {
Task { @MainActor in
searchBar.searchTextField.searchSuggestions = completer.results.map { result in
UISearchSuggestionItem(localizedSuggestion: result.title, localizedDescription: result.description)
}
}
}
Fix
I have made the errors go away by mapping the results properties to a tuple with just the String values I needed:
extension ViewController: MKLocalSearchCompleterDelegate {
nonisolated func completerDidUpdateResults(_ completer: MKLocalSearchCompleter) {
let results = completer.results.map { result in
(result.title, result.description)
}
Task { @MainActor in
searchBar.searchTextField.searchSuggestions = results.map { result in
UISearchSuggestionItem(localizedSuggestion: result.0, localizedDescription: result.1)
}
}
}
Why it works
My understanding is that since completer: MKLocalSearchCompleter and completer.results: [MKLocalSearchCompletion] are both classes (reference types) and not final, they are therefore NOT Sendable.
Strings, however, are value types, so they are Sendable and can be passed between isolation domains.
