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Alternative to CoreTelephony for Accessing Cellular Network Information in Private iOS App
Hello, I am developing a private internal Flutter app for our customer, which will not be published on the Apple Store. One of the key features of this app is to collect RF strength metrics to share user experience with the network. For Android, we successfully implemented the required functionality and are able to collect the following metrics: Signal strength level (0-4) Signal strength in dBm RSSI RSRQ Cell ID Location Area Code Carrier name Mobile country code Mobile network code Radio access technology Connection status Duplex mode However, for iOS, we are facing challenges with CoreTelephony, which is not returning the necessary data. We are aware that CoreTelephony is deprecated and are looking for alternatives. We noticed that a lot of the information we need is available via FTMInternal-4. Is there a way to access this data for a private app? Are there any other recommended approaches or frameworks that can be used to gather cellular network information on iOS for an app that won't be distributed via the Apple Store? my swift code import Foundation import CoreTelephony class RfSignalStrengthImpl: RfSignalStrengthApi { func getCellularSignalStrength(completion: @escaping (Result<CellularSignalStrength, Error>) -> Void) { let networkInfo = CTTelephonyNetworkInfo() guard let carrier = networkInfo.serviceSubscriberCellularProviders?.values.first else { completion(.failure(NSError(domain: "com.xxxx.yyyy", code: 0, userInfo: [NSLocalizedDescriptionKey: "Carrier not found"]))) return } let carrierName = carrier.carrierName ?? "Unknown" let mobileCountryCode = carrier.mobileCountryCode ?? "Unknown" let mobileNetworkCode = carrier.mobileNetworkCode ?? "Unknown" let radioAccessTechnology = networkInfo.serviceCurrentRadioAccessTechnology?.values.first ?? "Unknown" var connectionStatus = "Unknown" ... ... } Thank you for your assistance.
6
0
1.7k
May ’24
Cast Any to Sendable
I'm continuing with the migration towards Swift 6. Within one of our libraries, I want to check whether a parameter object: Any? confirms to Sendable. I tried the most obvious one: if let sendable = object as? Sendable { } But that results into the compiler error "Marker protocol 'Sendable' cannot be used in a conditional cast". Is there an other way to do this?
5
0
1.4k
Jul ’24
Link to a Precompiled Static C Library in a Swift Library Package
I want to build a Swift library package that uses modified build of OpenSSL and Curl. I have already statically compiled both and verified I can use them in an Objective-C framework on my target platform (iOS & iOS Simulator). I'm using XCFramework files that contain the static library binaries and headers: openssl.xcframework/ ios-arm64/ openssl.framework/ Headers/ [...] openssl ios-arm64_x86_64-simulator/ openssl.framework/ Headers/ [...] openssl Info.plist I'm not sure how I'm supposed to set up my Swift package to import these libraries. I can use .systemLibrary but that seems to use the embedded copies of libssl and libcurl on my system, and I can't figure out how to use the path: parameter to that. I also tried using a .binaryTarget pointing to the XCFramework files, but that didn't seem to work as there is no module generated and I'm not sure how to make one myself. At a basic high level, this is what I'm trying to accomplish: where libcrypto & libssl come from the provided openssl.xcframework file, and libcurl from curl.xcframework
8
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2.4k
Jul ’24
Weird crashes when accessing Swift Array
For some time now Xcode has been downloading crash reports from users of my app about crashes related to arrays. One of them looks like this: ... Code Type: ARM-64 Parent Process: launchd [1] User ID: 501 Date/Time: 2024-07-18 14:59:40.4375 +0800 OS Version: macOS 15.0 (24A5289h) ... Crashed Thread: 0 Exception Type: EXC_BREAKPOINT (SIGTRAP) Exception Codes: 0x0000000000000001, 0x00000001045048b8 Termination Reason: Namespace SIGNAL, Code 5 Trace/BPT trap: 5 Terminating Process: exc handler [1771] Thread 0 Crashed: 0 MyApp 0x00000001045048b8 specialized Collection.map<A>(_:) + 596 1 MyApp 0x00000001045011e4 MyViewController.validateToolbarButtons() + 648 (MyViewController.swift:742) ... The relevant code looks like this: class MyViewController { func validateToolbarButtons() { let indexes = tableView.clickedRow == -1 || tableView.selectedRowIndexes.contains(tableView.clickedRow) ? tableView.selectedRowIndexes : IndexSet(integer: tableView.clickedRow) let items = indexes.map({ myArray[$0] }) ... } } The second crash looks like this: ... Code Type: X86-64 (Native) Parent Process: launchd [1] User ID: 502 Date/Time: 2024-07-15 15:53:35.2229 -0400 OS Version: macOS 15.0 (24A5289h) ... Crashed Thread: 0 Exception Type: EXC_BAD_INSTRUCTION (SIGILL) Exception Codes: 0x0000000000000001, 0x0000000000000000 Termination Reason: Namespace SIGNAL, Code 4 Illegal instruction: 4 Terminating Process: exc handler [13244] Thread 0 Crashed: 0 libswiftCore.dylib 0x00007ff812904fc0 _assertionFailure(_:_:flags:) + 288 1 MyApp 0x0000000101a31e04 specialized _ArrayBuffer._getElementSlowPath(_:) + 516 2 MyApp 0x00000001019d04eb MyObject.myProperty.setter + 203 (MyObject.swift:706) 3 MyApp 0x000000010192f66e MyViewController.controlTextDidChange(_:) + 190 (MyViewController.swift:166) ... And the relevant code looks like this: class MyObject { var myProperty: [MyObject] { get { ... } set { let items = newValue.map({ $0.id }) ... } } } What could cause such crashes? Could they be caused by anything other than concurrent access from multiple threads (which I'm quite sure is not the case here, as I only access these arrays from the main thread)?
16
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2.1k
Jul ’24
@Observable class not compatible with Codable?
So any time I create a class that's both @Observable and Codable, e.g. @Observable class GameLocationManager : Codable { I get a warning in the macro expansion code: @ObservationIgnored private let _$observationRegistrar = Observation.ObservationRegistrar() Immutable property will not be decoded because it is declared with an initial value which cannot be overwritten. I've been ignoring them for now, but there are at least a half a dozen of them now in my (relatively small) codebase, and I'd like to find a solution (ideally one that doesn't require me to write init(decoder:) for every @Observable class in my project...), especially since I'm not sure what the actual consequences of ignoring this might be.
2
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907
Jul ’24
.onMove does not work properly
Hello, I have a problem with the .onMove function. I believe I have set everything up properly. However, the moving does not seem to be working correctly. When I try to move the item, it is highlighted first, as it is supposed to be. Then, while I am moving it through the list, it disappears for some reason, and at the end of the move, it comes back to its initial place. (I use iOS 16.0 minimum, so I don't have to include the EditButton(). It works the same in the edit mode tho) import SwiftUI struct Animal: Identifiable { var id = UUID() var name: String } struct ListMove: View { @State var animals = [Animal(name: "Dog"), Animal(name: "Cat"), Animal(name: "Cow"), Animal(name: "Goat"), Animal(name: "Chicken")] var body: some View { List { ForEach(animals) { animal in Text(animal.name) } .onMove(perform: move) } } func move(from source: IndexSet, to destination: Int) { animals.move(fromOffsets: source, toOffset: destination) } } #Preview { ListMove() }
3
2
1.1k
Aug ’24
Command SwiftCompile failed with a nonzero exit code. in xocde 16 and 15 where as it was working fine in xcode 14.3
My project’s source code was building, running, and archiving successfully in Xcode 14.3. However, after upgrading to Xcode 15, I began encountering the error: “Command SwiftCompile failed with a nonzero exit code.” I couldn't resolve the issue, so I decided to continue using Xcode 14.3. Recently, I upgraded to macOS Sequoia and also updated to Xcode 16. Unfortunately, the same error persists in the latest Xcode: “Command SwiftCompile failed with a nonzero exit code.” The unfortunate part is that Xcode 14.3 no longer works after the macOS upgrade. Whenever I try to run the code, I get the following popup.
10
0
3k
Sep ’24
Request authorization for the notification center crash iOS app on Swift 6
Hey all! During the migration of a production app to swift 6, I've encountered a problem: when hitting the UNUserNotificationCenter.current().requestAuthorization the app crashes. If I switch back to Language Version 5 the app works as expected. The offending code is defined here class AppDelegate: NSObject, UIApplicationDelegate { func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -&gt; Bool { FirebaseApp.configure() FirebaseConfiguration.shared.setLoggerLevel(.min) UNUserNotificationCenter.current().delegate = self let authOptions: UNAuthorizationOptions = [.alert, .badge, .sound] UNUserNotificationCenter.current().requestAuthorization(options: authOptions) { _, _ in } application.registerForRemoteNotifications() Messaging.messaging().delegate = self return true } } The error is depicted here: I have no idea how to fix this. Any help will be really appreciated thanks in advance
19
3
5.4k
Sep ’24
Collection and Index error on Xcode 16
Hi, After update to Xcode 16 a lot of errors happen, for example: import Foundation extension Collection {     func get(at i: Index) -&gt; Element? {         return indices.contains(i) ? self[i] : nil     } } Errors: Cannot find type 'Index' in scope Cannot find 'indices' in scope What is wrong? Thanks.
5
0
698
Sep ’24
MPMediaItemPropertyArtwork crashes on Swift 6
Hey all! in my personal quest to make future proof apps moving to Swift 6, one of my app has a problem when setting an artwork image in MPNowPlayingInfoCenter Here's what I'm using to set the metadata func setMetadata(title: String? = nil, artist: String? = nil, artwork: String? = nil) async throws { let defaultArtwork = UIImage(named: "logo")! var nowPlayingInfo = [ MPMediaItemPropertyTitle: title ?? "***", MPMediaItemPropertyArtist: artist ?? "***", MPMediaItemPropertyArtwork: MPMediaItemArtwork(boundsSize: defaultArtwork.size) { _ in defaultArtwork } ] as [String: Any] if let artwork = artwork { guard let url = URL(string: artwork) else { return } let (data, response) = try await URLSession.shared.data(from: url) guard (response as? HTTPURLResponse)?.statusCode == 200 else { return } guard let image = UIImage(data: data) else { return } nowPlayingInfo[MPMediaItemPropertyArtwork] = MPMediaItemArtwork(boundsSize: image.size) { _ in image } } MPNowPlayingInfoCenter.default().nowPlayingInfo = nowPlayingInfo } the app crashes when hitting MPMediaItemPropertyArtwork: MPMediaItemArtwork(boundsSize: defaultArtwork.size) { _ in defaultArtwork } or nowPlayingInfo[MPMediaItemPropertyArtwork] = MPMediaItemArtwork(boundsSize: image.size) { _ in image } commenting out these two make the app work again. Again, no clue on why. Thanks in advance
6
0
2.6k
Sep ’24
App crash on iPhone 11 Pro Max version 18.0 which build on Xcode 16.0
thread #1, stop reason = signal SIGABRT frame #0: 0x00000001a95985a8 dyld__abort_with_payload + 8 frame #1: 0x00000001a959f208 dyldabort_with_payload_wrapper_internal + 104 frame #2: 0x00000001a959f23c dyldabort_with_payload + 16 frame #3: 0x00000001a95364c8 dylddyld4::halt(char const*, dyld4::StructuredError const*) + 300 frame #4: 0x00000001a9541f60 dylddyld4::prepare(dyld4::APIs&, dyld3::MachOAnalyzer const*) + 4124 frame #5: 0x00000001a95667a8 dylddyld4::start(dyld4::KernelArgs*, void*, void*)::$_0::operator()() const + 544 frame #6: 0x00000001a955fb1c dyld`start + 2188
1
0
440
Sep ’24
Actor and the Singleton Pattern
As I migrate my apps to Swift 6 one by one, I am gaining a deeper understanding of concurrency. In the process, I am quite satisfied to see the performance benefits of parallel programming being integrated into my apps. At the same time, I have come to think that actor is a great type for addressing the 'data race' issues that can arise when using the 'singleton' pattern with class. Specifically, by using actor, you no longer need to write code like private let lock = DispatchQueue(label: "com.singleton.lock") to prevent data races that you would normally have to deal with when creating a singleton with a class. It reduces the risk of developer mistakes. import EventKit actor EKDataStore: Sendable { static let shared = EKDataStore() let eventStore: EKEventStore private init() { self.eventStore = EKEventStore() } } Of course, since a singleton is an object used globally, it can become harder to manage dependencies over time. There's also the downside of not being able to inject dependencies, which makes testing more difficult. I still think the singleton pattern is ideal for objects that need to be maintained throughout the entire lifecycle of the app with only one instance. The EKDataStore example I gave is such an object. I’d love to hear other iOS developers' opinions, and I would appreciate any advice on whether I might be missing something 🙏
1
0
1.5k
Sep ’24
Swift Testing not recognising tests
For my app I was trying to write some tests to ensure the functionality of all features. As I am using Xcode 16.0 I thought I might use Swift testing which was newly introduced and replaces XCTest. I created a new test target with Swift Testing and tried to run the first test, which was created automatically by the system. struct FinancialTests { @Test func testExample() async throws { #expect(true) } } Xcode is also showing the test diamond next to the function so I clicked on it to execute it. The app started to build and the build ended successfully. The the next step was testing. And after waiting for 10 minutes or so, no test was executed. First I thought maybe the test was not found, but in the test case overview all tests were shown: The run only shows this: Can someone help me to get this running. Many thanks!
3
1
1.1k
Sep ’24
Interpreting received "Data" object in cpp
Hello Everyone, I have a use case where I wanted to interpret the "Data" object received as a part of my NWConnection's recv call. I have my interpretation logic in cpp so in swift I extract the pointer to the raw bytes from Data and pass it to cpp as a UnsafeMutableRawPointer. In cpp it is received as a void * where I typecast it to char * to read data byte by byte before framing a response. I am able to get the pointer of the bytes by using // Swift Code // pContent is the received Data if let content = pContent, !content.isEmpty { bytes = content.withUnsafeBytes { rawBufferPointer in guard let buffer = rawBufferPointer.baseAddress else { // return with null data. } // invoke cpp method to interpret data and trigger response. } // Cpp Code void InterpretResponse (void * pDataPointer, int pDataLength) { char * data = (char *) pDataPointer; for (int iterator = 0; iterator < pDataLength; ++iterator ) { std::cout << data<< std::endl; data++; } } When I pass this buffer to cpp, I am unable to interpret it properly. Can someone help me out here? Thanks :) Harshal
4
0
947
Oct ’24
Can't link Obj-C Enum Symbol with DocC
Hi all, I am trying to use this guide to link directly to symbols in my documentation. But I am unable to get it to link to an Objective-C enum case. For example ``EnumNameType/EnumNameMyCase`` does not create a link. It works fine for method names, etc. I have tried all of the combinations I can think of, but I can't get it to work. Any help is much appreciated!
3
0
601
Oct ’24
Crash with Incorrect actor executor assumption
I'm seeing a crash compiling with Swift 6 that I can reproduce with the following code. It crashes with "Incorrect actor executor assumption". Is there something that the compiler should be warning about so that this isn't a runtime crash? Note - if I use a for in loop instead of the .forEach closure, the crash does not happen. Is the compiler somehow inferring the wrong isolation domain for the closure? import SwiftUI struct ContentView: View { var body: some View { Text("Hello, world!") .task { _ = try? await MyActor(store: MyStore()) } } } actor MyActor { var credentials = [String]() init(store: MyStore) async throws { try await store.persisted.forEach { credentials.append($0) } } } final class MyStore: Sendable { var persisted: [String] { get async throws { return ["abc"] } } } The stack trace is: * thread #6, queue = 'com.apple.root.user-initiated-qos.cooperative', stop reason = signal SIGABRT frame #0: 0x0000000101988f30 libsystem_kernel.dylib`__pthread_kill + 8 frame #1: 0x0000000100e2f124 libsystem_pthread.dylib`pthread_kill + 256 frame #2: 0x000000018016c4ec libsystem_c.dylib`abort + 104 frame #3: 0x00000002444c944c libswift_Concurrency.dylib`swift::swift_Concurrency_fatalErrorv(unsigned int, char const*, char*) + 28 frame #4: 0x00000002444c9468 libswift_Concurrency.dylib`swift::swift_Concurrency_fatalError(unsigned int, char const*, ...) + 28 frame #5: 0x00000002444c90e0 libswift_Concurrency.dylib`swift_task_checkIsolated + 152 frame #6: 0x00000002444c63e0 libswift_Concurrency.dylib`swift_task_isCurrentExecutorImpl(swift::SerialExecutorRef) + 284 frame #7: 0x0000000100d58944 IncorrectActorExecutorAssumption.debug.dylib`closure #1 in MyActor.init($0="abc") at <stdin>:0 frame #8: 0x0000000100d58b94 IncorrectActorExecutorAssumption.debug.dylib`partial apply for closure #1 in MyActor.init(store:) at <compiler-generated>:0 frame #9: 0x00000001947f8c80 libswiftCore.dylib`Swift.Sequence.forEach((τ_0_0.Element) throws -> ()) throws -> () + 428 * frame #10: 0x0000000100d58748 IncorrectActorExecutorAssumption.debug.dylib`MyActor.init(store=0x0000600000010ba0) at ContentView.swift:27:35 frame #11: 0x0000000100d57734 IncorrectActorExecutorAssumption.debug.dylib`closure #1 in ContentView.body.getter at ContentView.swift:14:32 frame #12: 0x0000000100d57734 IncorrectActorExecutorAssumption.debug.dylib`closure #1 in ContentView.body.getter at ContentView.swift:14:32 frame #13: 0x00000001d1817138 SwiftUI`(1) await resume partial function for partial apply forwarder for closure #1 () async -> () in closure #1 (inout Swift.TaskGroup<()>) async -> () in closure #1 () async -> () in SwiftUI.AppDelegate.application(_: __C.UIApplication, handleEventsForBackgroundURLSession: Swift.String, completionHandler: () -> ()) -> () frame #14: 0x00000001d17b1e48 SwiftUI`(1) await resume partial function for dispatch thunk of static SwiftUI.PreviewModifier.makeSharedContext() async throws -> τ_0_0.Context frame #15: 0x00000001d19c10c0 SwiftUI`(1) await resume partial function for generic specialization <()> of reabstraction thunk helper <τ_0_0 where τ_0_0: Swift.Sendable> from @escaping @isolated(any) @callee_guaranteed @async () -> (@out τ_0_0) to @escaping @callee_guaranteed @async () -> (@out τ_0_0, @error @owned Swift.Error) frame #16: 0x00000001d17b1e48 SwiftUI`(1) await resume partial function for dispatch thunk of static SwiftUI.PreviewModifier.makeSharedContext() async throws -> τ_0_0.Context
2
0
1.4k
Oct ’24
Casting `[String: Any]` to `[String: any Sendable]`
I have a simple wrapper class around WCSession to allow for easier unit testing. I'm trying to update it to Swift 6 concurrency standards, but running into some issues. One of them is in the sendMessage function (docs here It takes [String: Any] as a param, and returns them as the reply. Here's my code that calls this: @discardableResult public func sendMessage(_ message: [String: Any]) async throws -&gt; [String: Any] { return try await withCheckedThrowingContinuation { (continuation: CheckedContinuation&lt;[String: Any], Error&gt;) in wcSession.sendMessage(message) { response in continuation.resume(returning: response) // ERROR HERE } errorHandler: { error in continuation.resume(throwing: error) } } } However, I get this error: Sending 'response' risks causing data races; this is an error in the Swift 6 language mode Which I think is because Any is not Sendable. I tried casting [String: Any] to [String: any Sendable] but then it says: Conditional cast from '[String : Any]' to '[String : any Sendable]' always succeeds Any ideas on how to get this to work?
3
1
1.1k
Oct ’24
Crash with Progress type, Swift 6, iOS 18
We are getting a crash _dispatch_assert_queue_fail when the cancellationHandler on NSProgress is called. We do not see this with iOS 17.x, only on iOS 18. We are building in Swift 6 language mode and do not have any compiler warnings. We have a type whose init looks something like this: init( request: URLRequest, destinationURL: URL, session: URLSession ) { progress = Progress() progress.kind = .file progress.fileOperationKind = .downloading progress.fileURL = destinationURL progress.pausingHandler = { [weak self] in self?.setIsPaused(true) } progress.resumingHandler = { [weak self] in self?.setIsPaused(false) } progress.cancellationHandler = { [weak self] in self?.cancel() } When the progress is cancelled, and the cancellation handler is invoked. We get the crash. The crash is not reproducible 100% of the time, but it happens significantly often. Especially after cleaning and rebuilding and running our tests. * thread #4, queue = 'com.apple.root.default-qos', stop reason = EXC_BREAKPOINT (code=1, subcode=0x18017b0e8) * frame #0: 0x000000018017b0e8 libdispatch.dylib`_dispatch_assert_queue_fail + 116 frame #1: 0x000000018017b074 libdispatch.dylib`dispatch_assert_queue + 188 frame #2: 0x00000002444c63e0 libswift_Concurrency.dylib`swift_task_isCurrentExecutorImpl(swift::SerialExecutorRef) + 284 frame #3: 0x000000010b80bd84 MyTests`closure #3 in MyController.init() at MyController.swift:0 frame #4: 0x000000010b80bb04 MyTests`thunk for @escaping @callee_guaranteed @Sendable () -&gt; () at &lt;compiler-generated&gt;:0 frame #5: 0x00000001810276b0 Foundation`__20-[NSProgress cancel]_block_invoke_3 + 28 frame #6: 0x00000001801774ec libdispatch.dylib`_dispatch_call_block_and_release + 24 frame #7: 0x0000000180178de0 libdispatch.dylib`_dispatch_client_callout + 16 frame #8: 0x000000018018b7dc libdispatch.dylib`_dispatch_root_queue_drain + 1072 frame #9: 0x000000018018bf60 libdispatch.dylib`_dispatch_worker_thread2 + 232 frame #10: 0x00000001012a77d8 libsystem_pthread.dylib`_pthread_wqthread + 224 Any thoughts on why this is crashing and what we can do to work-around it? I have not been able to extract our code into a simple reproducible case yet. And I mostly see it when running our code in a testing environment (XCTest). Although I have been able to reproduce it running an app a few times, it's just less common.
24
7
2.6k
Oct ’24
Type ReferenceWritableKeyPath does not conform to the 'Sendable' protocol
This is not a question but more of a hint where I was having trouble with. In my SwiftData App I wanted to move from Swift 5 to Swift 6, for that, as recommended, I stayed in Swift 5 language mode and set 'Strict Concurrency Checking' to 'Complete' within my build settings. It marked all the places where I was using predicates with the following warning: Type '' does not conform to the 'Sendable' protocol; this is an error in the Swift 6 language mode I had the same warnings for SortDescriptors. I spend quite some time searching the web and wrapping my head around how to solve that issue to be able to move to Swift 6. In the end I found this existing issue in the repository of the Swift Language https://github.com/swiftlang/swift/issues/68943. It says that this is not a warning that should be seen by the developer and in fact when turning Swift 6 language mode on those issues are not marked as errors. So if anyone is encountering this when trying to fix all issues while staying in Swift 5 language mode, ignore those, fix the other issues and turn on Swift 6 language mode and hopefully they are gone.
3
1
991
Oct ’24