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In app purchase goes to Entered Billing Retry after free trail
I have a VPN application published in the app store. Used Ikev2 for this personal VPN. There are two in-app purchases. One is 'Monthly' and another is 'Yearly' with 3 days free trial. We have seen something strange for the yearly subscriptions which has free trail, the cancellation reason through the billing issue is too high like 70-80% due to billing retry state. Some other apps which have billing issues under 10% always. We have done some research and found that if the user doesn't cancel and Apple is unable to charge then it goes to a billing retry state. If users don't like the app, they could cancel their subscription/free trail easily but they are not doing this and why Apple unable to charge the bill after the trial ends. Am i missing something in the developer end?
3
0
1.1k
Dec ’24
Asynchronous json retrieval
Hello, I am getting an error message "Cannot convert value of type 'URLSessionDataTask' to expected argument type 'Data'" for the last line of this code. Please can you tell me what the problem is? Thank you struct Item : Codable { var id: String var name: String var country: String var type: String var overallrecsit: String var dlastupd: String var doverallrecsit: String } let url = URL(string:"https://www.TEST_URL.com/api_ios.php") let json = try? JSONDecoder().decode(Item.self, from: URLSession.shared.dataTask(with: url!))
1
0
327
Mar ’25
How to integrate data from a web service into an array
Hello, This test code for creating an array using a loop works: var quotes: [(id: String, name: String)] { var output: [(id: String, name: String)] = [] for i in 1...numberOfRows { let item: (id: String, name: String) = ("\(i)", "Name \(i)") output.append(item) } return output } But if I try to apply this logic to retrieving data from a web service using the below code I am getting 2 errors: For the line “quotes.append(item)” I am getting the error message “Cannot use mutating member on immutable value: ‘quotes’ is a get-only property." For the line “return output” I am getting the error message “Cannot find ‘output’ in scope." if let url = URL(string:"https://www.TEST.com/test_connection.php"){ URLSession.shared.dataTask(with: url) { (data, response, error) in if let data = data{ if let json = try? JSONDecoder().decode([[String:String]].self, from: data){ json.forEach { row in var item: (id: String, name: String) = ("test id value", "test name value") quotes.append(item) } return output } } } }
3
0
390
Mar ’25
Compiler exception when using Binding and Swift 6
In my code I use a binding that use 2 methods to get and get a value. There is no problem with swift 5 but when I swift to swift 6 the compiler fails : Here a sample example of code to reproduce the problem : `import SwiftUI struct ContentView: View { @State private var isOn = false var body: some View { VStack { Image(systemName: "globe") .imageScale(.large) .foregroundStyle(.tint) Text("Hello, world!") Toggle("change it", isOn: Binding(get: getValue, set: setValue(_:))) } .padding() } private func getValue() -> Bool { isOn } private func setValue(_ value: Bool) { isOn = value } }` Xcode compiler log error : 1. Apple Swift version 6.1.2 (swiftlang-6.1.2.1.2 clang-1700.0.13.5) 2. Compiling with the current language version 3. While evaluating request IRGenRequest(IR Generation for file "/Users/xavierrouet/Developer/TestCompilBindingSwift6/TestCompilBindingSwift6/ContentView.swift") 4. While emitting IR SIL function "@$sSbScA_pSgIeAghyg_SbIeAghn_TR". for <<debugloc at "<compiler-generated>":0:0>>Stack dump without symbol names (ensure you have llvm-symbolizer in your PATH or set the environment var LLVM_SYMBOLIZER_PATH` to point to it): 0 swift-frontend 0x000000010910ae24 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) + 56 1 swift-frontend 0x0000000109108c5c llvm::sys::RunSignalHandlers() + 112 2 swift-frontend 0x000000010910b460 SignalHandler(int) + 360 3 libsystem_platform.dylib 0x0000000188e60624 _sigtramp + 56 4 libsystem_pthread.dylib 0x0000000188e2688c pthread_kill + 296 5 libsystem_c.dylib 0x0000000188d2fc60 abort + 124 6 swift-frontend 0x00000001032ff9a8 swift::DiagnosticHelper::~DiagnosticHelper() + 0 7 swift-frontend 0x000000010907a878 llvm::report_fatal_error(llvm::Twine const&, bool) + 280 8 swift-frontend 0x00000001090aef6c report_at_maximum_capacity(unsigned long) + 0 9 swift-frontend 0x00000001090aec7c llvm::SmallVectorBase::grow_pod(void*, unsigned long, unsigned long) + 384 10 swift-frontend 0x000000010339c418 (anonymous namespace)::SyncCallEmission::setArgs(swift::irgen::Explosion&, bool, swift::irgen::WitnessMetadata*) + 892 11 swift-frontend 0x00000001035f8104 (anonymous namespace)::IRGenSILFunction::visitFullApplySite(swift::FullApplySite) + 4792 12 swift-frontend 0x00000001035c876c (anonymous namespace)::IRGenSILFunction::visitSILBasicBlock(swift::SILBasicBlock*) + 2636 13 swift-frontend 0x00000001035c6614 (anonymous namespace)::IRGenSILFunction::emitSILFunction() + 15860 14 swift-frontend 0x00000001035c2368 swift::irgen::IRGenModule::emitSILFunction(swift::SILFunction*) + 2788 15 swift-frontend 0x00000001033e7c1c swift::irgen::IRGenerator::emitLazyDefinitions() + 5288 16 swift-frontend 0x0000000103573d6c swift::IRGenRequest::evaluate(swift::Evaluator&, swift::IRGenDescriptor) const + 4528 17 swift-frontend 0x00000001035c15c4 swift::SimpleRequest<swift::IRGenRequest, swift::GeneratedModule (swift::IRGenDescriptor), (swift::RequestFlags)17>::evaluateRequest(swift::IRGenRequest const&, swift::Evaluator&) + 180 18 swift-frontend 0x000000010357d1b0 swift::IRGenRequest::OutputType swift::Evaluator::getResultUncached<swift::IRGenRequest, swift::IRGenRequest::OutputType swift::evaluateOrFatalswift::IRGenRequest(swift::Evaluator&, swift::IRGenRequest)::'lambda'()>(swift::IRGenRequest const&, swift::IRGenRequest::OutputType swift::evaluateOrFatalswift::IRGenRequest(swift::Evaluator&, swift::IRGenRequest)::'lambda'()) + 812 19 swift-frontend 0x0000000103576910 swift::performIRGeneration(swift::FileUnit*, swift::IRGenOptions const&, swift::TBDGenOptions const&, std::__1::unique_ptr<swift::SILModule, std::__1::default_deleteswift::SILModule>, llvm::StringRef, swift::PrimarySpecificPaths const&, llvm::StringRef, llvm::GlobalVariable**) + 176 20 swift-frontend 0x0000000102f61af0 generateIR(swift::IRGenOptions const&, swift::TBDGenOptions const&, std::__1::unique_ptr<swift::SILModule, std::__1::default_deleteswift::SILModule>, swift::PrimarySpecificPaths const&, llvm::StringRef, llvm::PointerUnion<swift::ModuleDecl*, swift::SourceFile*>, llvm::GlobalVariable*&, llvm::ArrayRef<std::__1::basic_string<char, std::__1::char_traits, std::__1::allocator>>) + 156 21 swift-frontend 0x0000000102f5d07c performCompileStepsPostSILGen(swift::CompilerInstance&, std::__1::unique_ptr<swift::SILModule, std::__1::default_deleteswift::SILModule>, llvm::PointerUnion<swift::ModuleDecl*, swift::SourceFile*>, swift::PrimarySpecificPaths const&, int&, swift::FrontendObserver*) + 2108 22 swift-frontend 0x0000000102f5c0a8 swift::performCompileStepsPostSema(swift::CompilerInstance&, int&, swift::FrontendObserver*) + 1036 23 swift-frontend 0x0000000102f5f654 performCompile(swift::CompilerInstance&, int&, swift::FrontendObserver*) + 1764 24 swift-frontend 0x0000000102f5dfd8 swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) + 3716 25 swift-frontend 0x0000000102ee20bc swift::mainEntry(int, char const**) + 5428 26 dyld 0x0000000188a86b98 start + 6076 Using Xcode 16.4 / Mac OS 16.4
4
0
1.3k
2w
Use FormatStyle to print formatted values from a Vector structure
I'm trying to use FormatStyle from Foundation to format numbers when printing a vector structure. See code below. import Foundation struct Vector<T> { var values: [T] subscript(item: Int) -> T { get { values[item] } set { values[item] = newValue } } } extension Vector: CustomStringConvertible { var description: String { var desc = "( " desc += values.map { "\($0)" }.joined(separator: " ") desc += " )" return desc } } extension Vector { func formatted<F: FormatStyle>(_ style: F) -> String where F.FormatInput == T, F.FormatOutput == String { var desc = "( " desc += values.map { style.format($0) }.joined(separator: " ") desc += " )" return desc } } In the example below, the vector contains a mix of integer and float literals. The result is a vector with a type of Vector<Double>. Since the values of the vector are inferred as Double then I expect the print output to display as decimal numbers. However, the .number formatted output seems to ignore the vector type and print the values as a mix of integers and decimals. This is fixed by explicitly providing a format style with a fraction length. So why is the .formatted(.number) method ignoring the vector type T which is Double in this example? let vec = Vector(values: [-2, 5.5, 100, 19, 4, 8.37]) print(vec) print(vec.formatted(.number)) print(vec.formatted(.number.precision(.fractionLength(1...)))) ( -2.0 5.5 100.0 19.0 4.0 8.37 ) // correct output that uses all Double types ( -2 5.5 100 19 4 8.37 ) // wrong output that uses Int and Double types ( -2.0 5.5 100.0 19.0 4.0 8.37 ) // correct output that uses all Double types
2
0
309
Mar ’25
Use of `for await` with `AyncStream`, and yielding async closures to its continuation
Hello, I was hoping to clarify my understanding of the use of for await with an AsyncStream. My use case is, I'd like to yield async closures to the stream's continuation, with the idea that, when I use for await with the stream to process and execute the closures, it would only continue on to the following closure once the current closure has been run to completion. At a high level, I am trying to implement in-order execution of async closures in the context of re-entrancy. An example of asynchronous work I want to execute is a network call that should write to a database: func syncWithRemote() async -> Void { let data = await fetchDataFromNetwork() await writeToLocalDatabase(data) } For the sake of example, I'll call the intended manager of closure submission SingleOperationRunner. where, at a use site such as this, my desired outcome is that call 1 of syncWithRemote() is always completed before call 2 of it: let singleOperationRunner = SingleOperationRunner(priority: nil) singleOperationRunner.run { syncWithRemote() } singleOperationRunner.run { syncWithRemote() } My sketch implementation looks like this: public final class SingleOperationRunner { private let continuation: AsyncStream<() async -> Void>.Continuation public init(priority: TaskPriority?) { let (stream, continuation) = AsyncStream.makeStream(of: (() async -> Void).self) self.continuation = continuation Task.detached(priority: priority) { // Will this loop only continue when the `await operation()` completes? for await operation in stream { await operation() } } } public func run(operation: @escaping () async -> Void) { continuation.yield(operation) } deinit { continuation.finish() } } The resources I've found are https://developer.apple.com/videos/play/wwdc2022-110351/?time=1445 and https://forums.swift.org/t/swift-async-func-to-run-sequentially/60939/2 but do not think I have fully put the pieces together, so would appreciate any help!
2
0
311
Mar ’25
App mysteriously crashing in CFNetwork.LoaderQ queue
I’m stuck with repeated production crashes in my SwiftUI app and I can’t make sense of the traces on my own. The symbolicated reports show the same pattern: Crash on com.apple.CFNetwork.LoaderQ with EXC_BAD_ACCESS / PAC failure Always deep in CFNetwork, most often in URLConnectionLoader::loadWithWhatToDo(NSURLRequest*, _CFCachedURLResponse const*, long, URLConnectionLoader::WhatToDo) No frames from my code, no sign of AuthManager or tokens. What I’ve tried: Enabled Address Sanitizer, Malloc Scribble, Guard Malloc, Zombies. Set CFNETWORK_DIAGNOSTICS=3 and collected Console logs. Stress-tested the app (rapid typing, filter switching, background/foreground, poor network with Network Link Conditioner). Could not reproduce the crash locally. So far: Logs show unrelated performance faults (I/O on main thread, CLLocationManager delegate), but no obvious CFNetwork misuse. My suspicion is a URLSession lifetime or delegate/auth-challenge race, but I can’t confirm because I can’t trigger it. Since starting this investigation, I also refactored some of my singletons into @State/@ObservedObject dependencies. For example, my app root now wires up AuthManager, BackendService, and AccountManager (where API calls happen using async/await) as @State properties: @State var authManager: AuthManager @State var accountManager: AccountManager @State var backendService: BackendService init() { let authManager = AuthManager() self._authManager = .init(wrappedValue: authManager) let backendService = BackendService(authManager: authManager) self._backendService = .init(wrappedValue: backendService) self._accountManager = .init(wrappedValue: AccountManager(backendService: backendService)) } I don’t know if this refactor is related to the crash, but I am including it to be complete. Apologies that I don’t have a minimized sample project — this issue seems app-wide, and all I have are the crash logs. Request: Given the crash location (URLConnectionLoader::loadWithWhatToDo), can Apple provide guidance on known scenarios or misuses that can lead to this crash? Is there a way to get more actionable diagnostics from CFNetwork beyond CFNETWORK_DIAGNOSTICS to pinpoint whether it’s session lifetime, cached response corruption, or auth/redirect? Can you also confirm whether my dependency setup above could contribute to URLSession or backend lifetime issues? I can’t reliably reproduce the crash, and without Apple’s insight the stack trace is effectively opaque to me. Thanks for your time and help. Happy to send multiple symbolicated crash logs at request. Thanks for any help. PS. Including 2 of many similar crash logs. Can provide more if needed. Atlans-2025-07-29-154915_symbolicated (cfloader).txt Atlans-2025-08-08-124226_symbolicated (cfloader).txt
5
0
4.0k
2w
How to run `xctest` bundle - or how to add `entitlement` to test?
I am writing a SPM based project for MacOS. In this project? I need to access MacOS Keychain. I am write a swift test built by SPM testTarget(). I can see it generates a bundle ./.build/x86_64-apple-macosx/debug/MyProjectTests.xctest with an executable: % file ./.build/x86_64-apple-macosx/debug/MyProjectPackageTests.xctest/Contents/MacOS/MyProjectPackageTests ./.build/x86_64-apple-macosx/debug/MyProjectPackageTests.xctest/Contents/MacOS/MyProjectPackageTests: Mach-O 64-bit bundle x86_64 This bundle file cannot be executed. How can I execute its tests? I tried with xcodebuild test-without-building -xctestrun ./.build/x86_64-apple-macosx/debug/MyProjectPackageTests.xctest -destination 'platform=macOS' without any chance. Obviously the next question is can I 'simply' add entitlement to this bundle with codesign to fix my enttilement error. My error when running the test is A required entitlement isn't present.
2
0
1.4k
Mar ’25
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
0
2.3k
Mar ’25
NSExpression error handling
Context: SwiftUI TextField with a String for simple math using NSExpression. I first prepare the input string to an extent but a malformed input using valid characters still fails, as expected. Let's say preparedExpression is "5--" let expr = NSExpression(format: preparedExpression) gives FAULT: NSInvalidArgumentException: Unable to parse the format string "5-- == 1"; (user info absent) How can I use NSExpression such that either the preparedExpression is pre-tested before asking for actual execution or the error is handled in a polite way that I can use to alert the user to try again. Is there a Swift alternative to NSExpression that I've missed?
3
0
531
Jan ’25
json array shows in debugger but can't parse
Hello, I have a json array showing in Xcode debugger (from the line "print(dataString)"): Optional("[{\"id\":\"8e8tfdcssu4u2hn7a71tkveahjhn8xghqcfkwf1bzvtrw5nu0b89w\",\"name\":\"Ameliana\",\"country\":\"France\",\"type\":\"Private\\/Corporate\",\"overallrecsit\":\"Positive\",\"dlastupd\":\"1741351633\",\"doverallrecsit\":\"1546848000\"},{\"id\":\"z69718a1a5z2y5czkwrhr1u37h7h768v05qr3pf1fegh4r4yrt5a68\",\"name\":\"Timberland\",\"country\":\"Switzerland\",\"type\":\"Charter\",\"overallrecsit\":\"Negative\",\"dlastupd\":\"1741351615\",\"doverallrecsit\":\"1740434582\"}, But my JSON decoder is throwing the catch error "Error in JSON parsing" This is the code: super.viewDidLoad() let urlString = "https://www.pilotjobsnetwork.com/service_ios.php" let url = URL(string: urlString) guard url != nil else { return } let session = URLSession.shared let dataTask = session.dataTask(with: url!) { (data, response, error) in var dataString = String(data: data!, encoding: String.Encoding.utf8) print(dataString) if error == nil &amp;&amp; data != nil { // Parse JSON let decoder = JSONDecoder() do { let newsFeed = try decoder.decode(NewsFeed.self, from: data!) print(newsFeed) print(error) } catch{ print("Error in JSON parsing") } } } // Make the API Call dataTask.resume() } And this is my Codable file NewsFeed.swift: struct NewsFeed: Codable { var id: String var name: String var country: String var type: String var overallrecsit: String var dlastupd: String var doverallrecsit: String } Please do you know why the parsing may be failing? Is it significant that in the debugging window the JSON is displaying backslashes before the quotation marks? Thank you for any pointers :-)
2
0
345
Mar ’25
How to implement thread-safe property wrapper notifications across different contexts in Swift?
I’m trying to create a property wrapper that that can manage shared state across any context, which can get notified if changes happen from somewhere else. I'm using mutex, and getting and setting values works great. However, I can't find a way to create an observer pattern that the property wrappers can use. The problem is that I can’t trigger a notification from a different thread/context, and have that notification get called on the correct thread of the parent object that the property wrapper is used within. I would like the property wrapper to work from anywhere: a SwiftUI view, an actor, or from a class that is created in the background. The notification preferably would get called synchronously if triggered from the same thread or actor, or otherwise asynchronously. I don’t have to worry about race conditions from the notification because the state only needs to reach eventuall consistency. Here's the simplified pseudo code of what I'm trying to accomplish: // A single source of truth storage container. final class MemoryShared<Value>: Sendable { let state = Mutex<Value>(0) func withLock(_ action: (inout Value) -> Void) { state.withLock(action) notifyObservers() } func get() -> Value func notifyObservers() func addObserver() } // Some shared state used across the app static let globalCount = MemoryShared<Int>(0) // A property wrapper to access the shared state and receive changes @propertyWrapper struct SharedState<Value> { public var wrappedValue: T { get { state.get() } nonmutating set { // Can't set directly } } var publisher: Publisher {} init(state: MemoryShared) { // ... } } // I'd like to use it in multiple places: @Observable class MyObservable { @SharedState(globalCount) var count: Int } actor MyBackgroundActor { @SharedState(globalCount) var count: Int } @MainActor struct MyView: View { @SharedState(globalCount) var count: Int } What I’ve Tried All of the examples below are using the property wrapper within a @MainActor class. However the same issue happens no matter what context I use the wrapper in: The notification callback is never called on the context the property wrapper was created with. I’ve tried using @isolated(any) to capture the context of the wrapper and save it to be called within the state in with unchecked sendable, which doesn’t work: final class MemoryShared<Value: Sendable>: Sendable { // Stores the callback for later. public func subscribe(callback: @escaping @isolated(any) (Value) -> Void) -> Subscription } @propertyWrapper struct SharedState<Value> { init(state: MemoryShared<Value>) { MainActor.assertIsolated() // Works! state.subscribe { MainActor.assertIsolated() // Fails self.publisher.send() } } } I’ve tried capturing the isolation within a task with AsyncStream. This actually compiles with no sendable issues, but still fails: @propertyWrapper struct SharedState<Value> { init(isolation: isolated (any Actor)? = #isolation, state: MemoryShared<Value>) { let (taskStream, continuation) = AsyncStream<Value>.makeStream() // The shared state sends new values to the continuation. subscription = state.subscribe(continuation: continuation) MainActor.assertIsolated() // Works! let task = Task { _ = isolation for await value in taskStream { _ = isolation MainActor.assertIsolated() // Fails } } } } I’ve tried using multiple combine subjects and publishers: final class MemoryShared<Value: Sendable>: Sendable { let subject: PassthroughSubject<T, Never> // ... var publisher: Publisher {} // ... } @propertyWrapper final class SharedState<Value> { var localSubject: Subject init(state: MemoryShared<Value>) { MainActor.assertIsolated() // Works! handle = localSubject.sink { MainActor.assertIsolated() // Fails } stateHandle = state.publisher.subscribe(localSubject) } } I’ve also tried: Using NotificationCenter Making the property wrapper a class Using NSKeyValueObserving Using a box class that is stored within the wrapper. Using @_inheritActorContext. All of these don’t work, because the event is never called from the thread the property wrapper resides in. Is it possible at all to create an observation system that notifies the observer from the same context as where the observer was created? Any help would be greatly appreciated!
2
0
540
Mar ’25
Manually calling the superclass's dealloc in the overridden dealloc method causes a crash
I have a class object created dynamically using Runtime, and I want to release some manually allocated memory resources when this object is deallocated. To achieve this, I added a custom implementation of the dealloc method using the following code: SEL aSel = NSSelectorFromString(@"dealloc"); class_addMethod(kvoClass, aSel, (IMP)custom_dealloc, method_getTypeEncoding(class_getInstanceMethod(kvoClass, aSel))); However, I encountered some issues. If I don't call the superclass's dealloc method in the cus_dealloc function, the superclass's dealloc implementation will not be executed. On the other hand, if I explicitly call the superclass's dealloc method, the program crashes. Here is the implementation of the cus_dealloc function: void custom_dealloc(id self, SEL _cmd) { // Release other memory ![]("https://developer.apple.com/forums/content/attachment/c7b0c16b-be23-4776-b8db-f22b661c5e7d" "title=iShot_2025-01-03_19.31.34.png;width=1080;height=1895") Class superClass = class_getSuperclass(object_getClass(self)); void (*originIMP)(struct objc_super *, SEL, ...) = (void *)objc_msgSendSuper; struct objc_super *objcSuper = &(struct objc_super){self, superClass}; originIMP(objcSuper, _cmd); } demo
3
0
723
Jan ’25
Using `@ObservedObject` in a function
No real intruduction for this, so I'll get to the point: All this code is on GitHub: https://github.com/the-trumpeter/Timetaber-for-iWatch But first, sorry; /* I got roasted, last time I posted; for not defining my stuff. This'll be different, but's gonna be rough; 'cuz there's lots and lots to get through: */ //this is 'Timetaber Watch App/Define (No expressions)/Courses_vDef.swift' on the GitHub: struct Course { let name: String let icon: String let room: String let colour: String let listName: String let listIcon: String let joke: String init(name: String, icon: String, room: String? = nil, colour: String, listName: String? = nil, listIcon: String? = nil, joke: String? = nil) { self.name = name self.icon = icon self.room = room ?? "None" self.colour = colour self.listName = listName ?? name self.listIcon = listIcon ?? (icon+".circle.fill") self.joke = joke ?? "" } } //this is 'Timetaber Watch App/TimeManager_fDef.swift' on the GitHub: func getCurrentClass(date: Date) -> Array<Course> { //returns the course in session depending on the input date //it is VERY long but //all you really need to know is what it returns: //basically: return [rightNow, nextUp] } /* I thought that poetry would be okay, But poorly thought things through: For I'll probably find that people online will treat my rhymes like spew. */ So into the question: I have a bunch of views, all (intendedly) watching two variables inside of a class: //Github: 'Timetaber Watch App/TimetaberApp.swift' class GlobalData: ObservableObject { @Published var currentCourse: Course = getCurrentClass(date: .now)[0] // the current timetabled class in session. @Published var nextCourse: Course = getCurrentClass(date: .now)[1] // the next timetabled class in session } ...and a bunch of views using them in different ways as follows: (Sorry, don't have the characters to define functions called in these) import SwiftUI //Github: 'Timetaber Watch App/Views/HomeView.swift' struct HomeView: View { @StateObject var data = GlobalData() var body: some View { //HERE: let icon = data.currentCourse.icon let name = data.currentCourse.name let colour = data.currentCourse.colour let room = roomOrBlank(course: data.currentCourse) let next = data.nextCourse VStack { //CURRENT CLASS Image(systemName: icon) .foregroundColor(Color(colour))//add an SF symbol element .imageScale(.large) .font(.system(size: 25).weight(.semibold)) Text(name) .font(.system(size:23).weight(.bold)) .foregroundColor(Color(colour)) .padding(.bottom, 0.1) //ROOM Text(room+"\n") .multilineTextAlignment(.center) .foregroundStyle(.gray) .font(.system(size: 15)) if next.name != noSchool.name { Spacer() //NEXT CLASS Text(nextPrefix(course: next)) .font(.system(size: 15)) Text(getNextString(course: next)) .font(.system(size: 15)) .multilineTextAlignment(.center) } }.padding() } } // Github: 'Timetaber Watch App/Views/ListView.swift' struct listTemplate: View { @StateObject var data = GlobalData() var listedCourse: Course = failCourse(feedback: "lT.12") var courseTime: String = "" init(course: Course, courseTime: String) { self.courseTime = courseTime self.listedCourse = course } var body: some View { let localroom = if listedCourse.room == "None" { "" } else { listedCourse.room } let image = if listedCourse.listIcon == "custom1" { Image(.paintbrushPointedCircleFill) } else { Image(systemName: listedCourse.listIcon) } HStack{ image .foregroundColor(Color(listedCourse.colour)) .padding(.leading, 5) Text(listedCourse.name) .bold() Spacer() Text(courseTime) Text(localroom).bold().padding(.trailing, 5) } .padding(.bottom, 1) .background(data.currentCourse.name==listedCourse.name ? Color(listedCourse.colour).colorInvert(): nil) //HERE } } struct listedDay: View { let day: Dictionary<Int, Course> var body: some View { let dayKeys = Array(day.keys).sorted(by: <) List { ForEach((0...dayKeys.count-2), id: \.self) { let num = $0 listTemplate(course: day[dayKeys[num]] ?? failCourse(feedback: "lD.53"), courseTime: time24toNormal(time24: dayKeys[num])) } } } } struct ListView: View { var body: some View { if storage.shared.termRunningGB && weekdayFunc(inDate: .now) != 1 && weekdayFunc(inDate: .now) != 7 { ScrollView { listedDay( day: getTimetableDay( isWeekA: getIfWeekIsA_FromDateAndGhost( originDate: .now, ghostWeek: storage.shared.ghostWeekGB ), weekDay: weekdayFunc(inDate: .now) ) ) } } else if !storage.shared.termRunningGB { Text("There's no term running.\nThe day's classes will be displayed here.") .multilineTextAlignment(.center) .foregroundStyle(.gray) .font(.system(size: 13)) } else { Text("No school today.\nThe day's classes will be displayed here.") .multilineTextAlignment(.center) .foregroundStyle(.gray) .font(.system(size: 13)) } } } //There's one more view but I can't fit it for characters. //On GitHub: 'Timetaber Watch App/Views/SettingsView.swift' So... THE FUNCTION: This function is called when changes are made that will affect the correct output of getCurrentClass. It is intended to reload the views and the current/next variables to reflect those changes.\ //GHub: 'Timetaber Watch App/StorageManager.swift' func reload() -> Void { @ObservedObject var globalData: GlobalData //this line is erroring, I don't know how to fix it. Is this even the best/proper way to do this? let courseData = getCurrentClass(date: .now) globalData.currentCourse = courseData[0] globalData.nextCourse = courseData[1] //Variable '_globalData' used by function definition before being initialized //that is the error appearing on those above two redefinitions. print("Setup done\n") } Thanks! -Gill
1
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287
Mar ’25
json array shows in debugger but can't parse
Hello, I asked this question on 9th March but was asked to provide a project file and can't edit the original post. Please find the original question below and please find the new test project file at https://we.tl/t-fqAu8FrgUw. I have a json array showing in Xcode debugger (from the line "print(dataString)"): Optional("[{\"id\":\"8e8tcssu4u2hn7a71tkveahjhn8xghqcfkwf1bzvtrw5nu0b89w\",\"name\":\"Test name 0\",\"country\":\"Test country 0\",\"type\":\"Test type 0\",\"situation\":\"Test situation 0\",\"timestamp\":\"1546848000\"},{\"id\":\"z69718a1a5z2y5czkwrhr1u37h7h768v05qr3pf1h4r4yrt5a68\",\"name\":\"Test name 1\",\"country\":\"Test country 1\",\"type\":\"Test type 1\",\"situation\":\"Test situation 1\",\"timestamp\":\"1741351615\"},{\"id\":\"fh974sv586nhyysbhg5nak444968h7hgcgh6yw0usbvcz9b0h69\",\"name\":\"Test name 2\",\"country\":\"Test country 2\",\"type\":\"Test type 2\",\"situation\":\"Test situation 2\",\"timestamp\":\"1741351603\"},{\"id\":\"347272052385993\",\"name\":\"Test name 3\",\"country\":\"Test country 3\",\"type\":\"Test type 3\",\"situation\":\"Test situation 3\",\"timestamp\":\"1741351557\"}]") But my JSON decoder is throwing the catch error "Error in JSON parsing" This is the code: let urlString = "https://www.notafunnyname.com/jsonmockup.php" let url = URL(string: urlString) guard url != nil else { return } let session = URLSession.shared let dataTask = session.dataTask(with: url!) { (data, response, error) in var dataString = String(data: data!, encoding: String.Encoding.utf8) print(dataString) if error == nil && data != nil { // Parse JSON let decoder = JSONDecoder() do { let newsFeed = try decoder.decode(NewsFeed.self, from: data!) print(newsFeed) print(error) } catch{ print("Error in JSON parsing") } } } // Make the API Call dataTask.resume() } And this is my Codable file NewsFeed.swift: struct NewsFeed: Codable { var id: String var name: String var country: String var type: String var overallrecsit: String var dlastupd: String var doverallrecsit: String } Please do you know why the parsing may be failing? Is it significant that in the debugging window the JSON is displaying backslashes before the quotation marks? Thank you for any pointers :-)
1
0
344
Mar ’25
Can't access C/C++ basic libraries
Hello, I am a software engineer student and I have recently been getting problems on my Mac regarding the C/C++ libraries. I have used my macbook for uni work for months, but around 3 or 4 months ago my macbook could not compile my work since it couldnt find the basic libraries I was using. For example, iostream. I have been using VSCode, and what it exactly says is "cannot open source file "iostream". Please run the 'Select IntelliSense Configuration...' command to locate your system headers." I have tried researching, changing the include path, even using chatgpt, and nothing. Is anyone having this same problem, or is able to help me? If any other information is needed, please let me know!
1
0
767
Jan ’25
Async function doesn’t see external changes to an inout Bool in Release build
Title Why doesn’t this async function see external changes to an inout Bool in Release builds (but works in Debug)? Body I have a small helper function that waits for a Bool flag to become true with a timeout: public func test(binding value: inout Bool, timeout maximum: Int) async throws { var count = 0 while value == false { count += 1 try await Task.sleep(nanoseconds: 0_100_000_000) if value == true { return } if count > (maximum * 10) { return } } } I call like this: var isVPNConnected = false adapter.start(tunnelConfiguration: tunnelConfiguration) { [weak self] adapterError in guard let self = self else { return } if let adapterError = adapterError { } else { isVPNConnected = true } completionHandler(adapterError) } try await waitUntilTrue(binding: &isVPNConnected, timeout: 10) What I expect: test should keep looping until flag becomes true (or the timeout is hit). When the second task sets flag = true, the first task should see that change and return. What actually happens: In Debug builds this behaves as expected: when the second task sets flag = true, the loop inside test eventually exits. In Release builds the function often never sees the change and gets stuck until the timeout (or forever, depending on the code). It looks like the while value == false condition is using some cached value and never observes the external write. So my questions are: Is the compiler allowed to assume that value (the inout Bool) does not change inside the loop, even though there are await suspension points and another task is mutating the same variable? Is this behavior officially “undefined” because I’m sharing a plain Bool across tasks without any synchronization (actors / locks / atomics), so the debug build just happens to work? What is the correct / idiomatic way in Swift concurrency to implement this kind of “wait until flag becomes true with timeout” pattern? Should I avoid inout here completely and use some other primitive (e.g. AsyncStream, CheckedContinuation, Actor, ManagedAtomic, etc.)? Is there any way to force the compiler to re-read the Bool from memory each iteration, or is that the wrong way to think about it? Environment (if it matters): Swift: [fill in your Swift version] Xcode: [fill in your Xcode version] Target: iOS / macOS [fill in as needed] Optimization: default Debug vs. Release settings I’d like to understand why Debug vs Release behaves differently here, and what the recommended design is for this kind of async waiting logic in Swift.
2
0
1.1k
Nov ’25
json array shows in debugger but can't parse (corrected question)
Hello, Please see the test project at https://we.tl/t-aWAu7kk9lD I have a json array showing in Xcode debugger (from the line "print(dataString)"): Optional("[{\"id\":\"8e8tcssu4u2hn7a71tkveahjhn8xghqcfkwf1bzvtrw5nu0b89w\",\"name\":\"Test name 0\",\"country\":\"Test country 0\",\"type\":\"Test type 0\",\"situation\":\"Test situation 0\",\"timestamp\":\"1546848000\"},{\"id\":\"z69718a1a5z2y5czkwrhr1u37h7h768v05qr3pf1h4r4yrt5a68\",\"name\":\"Test name 1\",\"country\":\"Test country 1\",\"type\":\"Test type 1\",\"situation\":\"Test situation 1\",\"timestamp\":\"1741351615\"},{\"id\":\"fh974sv586nhyysbhg5nak444968h7hgcgh6yw0usbvcz9b0h69\",\"name\":\"Test name 2\",\"country\":\"Test country 2\",\"type\":\"Test type 2\",\"situation\":\"Test situation 2\",\"timestamp\":\"1741351603\"},{\"id\":\"347272052385993\",\"name\":\"Test name 3\",\"country\":\"Test country 3\",\"type\":\"Test type 3\",\"situation\":\"Test situation 3\",\"timestamp\":\"1741351557\"}]") But my JSON decoder is throwing a catch error Line 57, Error in JSON parsing typeMismatch(Swift.Dictionary<Swift.String, Any>, Swift.DecodingError.Context(codingPath: [], debugDescription: "Expected to decode Dictionary<String, Any> but found an array instead.", underlyingError: nil)) This is the code: let urlString = "https://www.notafunnyname.com/jsonmockup.php" let url = URL(string: urlString) guard url != nil else { return } let session = URLSession.shared let dataTask = session.dataTask(with: url!) { (data, response, error) in var dataString = String(data: data!, encoding: String.Encoding.utf8) print(dataString) if error == nil && data != nil { // Parse JSON let decoder = JSONDecoder() do { let newsFeed = try decoder.decode(NewsFeed.self, from: data!) print("line 51") print(newsFeed) print(error) } catch{ print("Line 57, Error in JSON parsing") print(error) } } } // Make the API Call dataTask.resume() } And this is my Codable file NewsFeed.swift: struct NewsFeed: Codable { var id: String var name: String var country: String var type: String var situation: String var timestamp: String } Please do you know how to resolve the typeMismatch error?
2
0
349
Mar ’25