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TaskExecutor and Swift 6 question
I have the following TaskExecutor code in Swift 6 and is getting the following error: //Error Passing closure as a sending parameter risks causing data races between main actor-isolated code and concurrent execution of the closure. May I know what is the best way to approach this? This is the default code generated by Xcode when creating a Vision Pro App using Metal as the Immersive Renderer. Renderer @MainActor static func startRenderLoop(_ layerRenderer: LayerRenderer, appModel: AppModel) { Task(executorPreference: RendererTaskExecutor.shared) { //Error let renderer = Renderer(layerRenderer, appModel: appModel) await renderer.startARSession() await renderer.renderLoop() } } final class RendererTaskExecutor: TaskExecutor { private let queue = DispatchQueue(label: "RenderThreadQueue", qos: .userInteractive) func enqueue(_ job: UnownedJob) { queue.async { job.runSynchronously(on: self.asUnownedSerialExecutor()) } } func asUnownedSerialExecutor() -> UnownedTaskExecutor { return UnownedTaskExecutor(ordinary: self) } static let shared: RendererTaskExecutor = RendererTaskExecutor() }
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834
Dec ’24
orientation transaction token
Hello Im having an error in swiftUI project of mine. I use fullscreencover to navigate through views. Normally it s been working but one point it doesn't. I go through MainMenu -> SomeOtherView -> GameView -> AfterGameView -> SomeOtherView -> MainMenu. When it comes to mainmenu at last, it s showing main menu for a glimpse of a look and then goes back to GameView. In console an error took my notice. > A new orientation transaction token is being requested while a valid one already exists. reason=Fullscreen transition (dismissing): fromVC=<_TtGC7SwiftUI29PresentationHostingControllerVS_7AnyView_: 0x10795ca00>; toVC=<_TtGC7SwiftUI29PresentationHostingControllerVS_7AnyView_: 0x1071c3400>;; windowOrientation=portrait; sceneOrientation=portrait; existingTransaction=<_UIForcedOrientationTransactionToken: 0x600001804a40; state: active; originalOrientation: portrait (1)> Cant really finding the solution. Need help asap I will release a bug update to Appstore.
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457
Jan ’25
error handling - Xcode shows error since Xcode Version > 15
Hello together, since Xcode Version > 15 the following error handling causes following error "Pattern of type 'DecodingError' cannot match 'Never' func getSupportedCountries() async { // fetch all documents from collection "seasons" from firestore let queryCountries = try? await db.collection("countries").getDocuments() if queryCountries != nil { self.countries = (queryCountries!.documents.compactMap({ (queryDocumentSnapshot) -> Country? in let result = Result { try? queryDocumentSnapshot.data(as: Country.self) } switch result { case .success(let country): if let country = country { // A country value was successfully initialized from the DocumentSnapshot self.errorMessage = nil return country } else { // A nil value was successfully initialized from the DocumentSnapshot, // or the DocumentSnapshot was nil self.errorMessage = "Document doesn't exist." return nil } case .failure(let error): // A Country value could not be initialized from the DocumentSnapshot switch error { case DecodingError.typeMismatch(_, let context): self.errorMessage = "\(error.localizedDescription): \(context.debugDescription)" case DecodingError.valueNotFound(_, let context): self.errorMessage = "\(error.localizedDescription): \(context.debugDescription)" case DecodingError.keyNotFound(_, let context): self.errorMessage = "\(error.localizedDescription): \(context.debugDescription)" case DecodingError.dataCorrupted(let key): self.errorMessage = "\(error.localizedDescription): \(key)" default: self.errorMessage = "Error decoding document: \(error.localizedDescription)" } return nil } })) } else { self.errorMessage = "No documents in 'countries' collection" return } } the interesting part of the code where XCODE shows an error is from "switch error" downwards. Does anyone of you have an idea what's wrong? Ay help appreciated ! Thx, Peter
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335
Jan ’25
Polynomial Coefficients calculation
How can I calculate polynomial coefficients for Tone Curve points: // • Red channel: (0, 0), (60, 39), (128, 128), (255, 255) // • Green channel: (0, 0), (63, 50), (128, 128), (255, 255) // • Blue channel: (0, 0), (60, 47), (119, 119), (255, 255) CIFilter: func colorCrossPolynomial(inputImage: CIImage) -> CIImage? { let colorCrossPolynomial = CIFilter.colorCrossPolynomial() let redfloatArr: [CGFloat] = [1, 1, 1, 1, 0, 0, 0, 0, 0, 0] let greenfloatArr: [CGFloat] = [0, 1, 1, 0, 0, 0, 0, 0, 0, 1] let bluefloatArr: [CGFloat] = [0, 0, 1, 0, 0, 0, 0, 1, 1, 0] colorCrossPolynomial.inputImage = inputImage colorCrossPolynomial.blueCoefficients = CIVector(values: bluefloatArr, count: bluefloatArr.count) colorCrossPolynomial.redCoefficients = CIVector(values: redfloatArr, count: redfloatArr.count) colorCrossPolynomial.greenCoefficients = CIVector(values: greenfloatArr, count: greenfloatArr.count) return colorCrossPolynomial.outputImage }
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443
Jan ’25
Swift6 race warning
I'm trying to fix some Swift6 warnings, this one seems too strict, I'm not sure how to fix it. The variable path is a String, which should be immutable, it's a local variable and never used again inside of the function, but still Swift6 complains about it being a race condition, passing it to the task What should I do here to fix the warning?
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602
Jan ’25
Causes of disordered dictionary in Swift
Everyone knows that dictionaries in swift are unordered collections, there is no problem with that. I've noticed some behavior that I can't explain and hope someone can help me. The first variant We have a very simple code: struct Test { let dict = [1: “1”, 2: “2”, 3: “3”, 4: “4”, 5: “5”] func test() { for i in dict { print(i) } } } If you call test() several times in a row, the output to the console on my computer looks something like this: (key: 5, value: “5”) (key: 1, value: “1”) (key: 2, value: “2”) (key: 3, value: “3”) (key: 4, value: “4”) (key: 2, value: “2”) (key: 3, value: “3”) (key: 1, value: “1”) (key: 4, value: “4”) (key: 5, value: “5”) (key: 1, value: “1”) (key: 3, value: “3”) (key: 2, value: “2”) (key: 5, value: “5”) (key: 4, value: “4”) At each new for loop we get a random order of elements It seemed logical to me, because a dictionary is an unordered collection and this is correct behavior. However The second variant the same code on my colleague's computer, but in the console we see something like this: (key: 2, value: “2”) (key: 3, value: “3”) (key: 1, value: “1”) (key: 4, value: “4”) (key: 5, value: “5”) (key: 2, value: “2”) (key: 3, value: “3”) (key: 1, value: “1”) (key: 4, value: “4”) (key: 5, value: “5”) (key: 2, value: “2”) (key: 3, value: “3”) (key: 1, value: “1”) (key: 4, value: “4”) (key: 5, value: “5”) always, within the same session, we get the same order in print(i) We didn't use Playground, within which there may be differences, but a real project. swift version 5+ we tested on Xcode 14+, 15+ (at first I thought it was because the first version had 14 and the second version had 15, but then a third colleague with Xcode 15 had the behavior from the first scenario) we did a lot of checks, several dozens of times and always got that on one computer random output of items to the console, and in another case disordered only in the first output to the console Thanks
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Dec ’24
Swift playground
Hi, I want to create a dashboard in a app using swift playgrounds with esp 32 and a led. The dashboard should have a toggle switch to toggle the switch state like on/off for the led once i get the basics i want to create a full dashboards with things like gauges, sliders, button and many more. Can someone please help/guide me. Thanks.
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311
Dec ’24
Swift Package Manager – Support for Multiple Targets with Distinct Localization Files
I am an SDK provider working with Swift Package Manager (SPM) to deliver libraries for iOS developers. My SDK currently uses SPM targets to modularize functionality. However, SPM enforces strict resource bundling, which prevents me from efficiently offering multiple targets—each with a different set of localization files—in a single package. Current Limitation: When multiple SPM targets share the same source and resource directory but require distinct sets of .lproj localization folders (for app size or client requirements), SPM raises “overlapping sources” errors. The only workaround is to manually split resource directories or have clients prune localizations post-build, which is inefficient and error-prone. Feature Request: Please consider adding native support in Swift Package Manager for: Defining multiple targets within a single package that can process overlapping source/resource directories, Each target specifying a distinct subset of localization resource files via the exclude or a new designated parameter, Enabling efficient modular delivery of SDKs to clients needing different localization payloads, without redundant resource duplication or error-prone manual pruning. Support for this feature would greatly ease SDK distribution, lower app sizes, and improve package maintainability for iOS and all Swift platforms.
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894
Sep ’25
Swift 6 and 5 - Strict concurrency: complete and WKNavigationDelegate decidePolicyFor not being called.
decidePolicyFor delegate method: import WebKit @objc extension DocumentationVC { func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) Being called just alright in swift 5 minimal concurrency. Raising concurrency to complete with swift 5 or swift 6. Changing the code to avoid warnings: @preconcurrency import WebKit @objc extension DocumentationVC { func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) { The delegate method is not being called. Changing back to swift 5 concurrency minimal - it is called. Looking at WKNavigationDelegate: WK_SWIFT_UI_ACTOR @protocol WKNavigationDelegate <NSObject> - (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(WK_SWIFT_UI_ACTOR void (^)(WKNavigationActionPolicy))decisionHandler WK_SWIFT_ASYNC(3); Changing the delegate method to: func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping @MainActor (WKNavigationActionPolicy) -> Void) { And it is called across swift 5 concurrency minimal to complete to swift 6. I thought, the meaning of @preconcurrency import WebKit was to keep the delegate without @MainActor before the (WKNavigationActionPolicy) still matching regardless the swift concurrency mode? My point is - this can introduce hidden breaking changes? I didn't see this documented anyhow at: https://www.swift.org/migration/documentation/migrationguide/. decidePolicyFor is an optional method - so if signature 'mismatches' - there will be no warning on not-implementing the delegate method. How do we catch or diagnose irregularities like this? Is it something @preconcurrency import WebKit should be ensuring and it is not? Is this delegate mismatch a bug on swift side or something we should be taking care of while migrating? If it is on us, how do we diagnose these potential mismatches?
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602
Jan ’25
Programming Languages Resources
This topic area is about the programming languages themselves, not about any specific API or tool. If you have an API question, go to the top level and look for a subtopic for that API. If you have a question about Apple developer tools, start in the Developer Tools & Services topic. For Swift questions: If your question is about the SwiftUI framework, start in UI Frameworks > SwiftUI. If your question is specific to the Swift Playground app, ask over in Developer Tools & Services > Swift Playground If you’re interested in the Swift open source effort — that includes the evolution of the language, the open source tools and libraries, and Swift on non-Apple platforms — check out Swift Forums If your question is about the Swift language, that’s on topic for Programming Languages > Swift, but you might have more luck asking it in Swift Forums > Using Swift. General: Forums topic: Programming Languages Swift: Forums subtopic: Programming Languages > Swift Forums tags: Swift Developer > Swift website Swift Programming Language website The Swift Programming Language documentation Swift Forums website, and specifically Swift Forums > Using Swift Swift Package Index website Concurrency Resources, which covers Swift concurrency How to think properly about binding memory Swift Forums thread Other: Forums subtopic: Programming Languages > Generic Forums tags: Objective-C Programming with Objective-C archived documentation Objective-C Runtime documentation Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com"
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818
Oct ’25
Beginner’s question on learning philosophy.
Hello Everyone! I started programming 6 months ago and started Swift / IOS last month. My learning so far has mainly been with Python. I learned a lot of the package ‘SQLAlchemy’, which has very ‘example based’ documentation. If I wanted to learn how to make a many to many relationship, there was a demonstration with code. But going into Swift and Apple packages, I notice most of the documentation is definitions of structures, modifiers, functions, etc. I wanted to make the equivalent of python ‘date times’ in my swift app. I found the section in the documentation “Foundation->Dates & Times”, but I couldn’t figure how to use that in my code. I assume my goal should not be to memorize every Swift and apple functionality by memory to be an app developer. So I would appreciate advice on how to approach this aspect of learning programming.
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436
Oct ’25
App Rejected: Non-Public Symbols _lzma_code and _lzma_end in Payload/Hogs.app/Hogs
I recently submitted my app, Hogs, to the App Store, but it was rejected due to references to non-public symbols: _lzma_code _lzma_end I am using the LZMA compression library in my app, and these functions are part of that implementation. Here's a breakdown of my usage: Library Used: liblzma (custom wrapper around LZMA functions) Error Message: "The app references non-public symbols in Payload/Hogs.app/Hogs: _lzma_code, _lzma_end." Steps I’ve Taken: I’ve wrapped the LZMA functions in my own functions (my_lzma_code, my_lzma_end) to prevent direct references. I have checked the build settings and included -lzma in the linker flags. I’ve tried using a custom framework to encapsulate LZMA, but the issue persists. I would greatly appreciate any help or suggestions on how to resolve this issue and get my app approved. Is there any workaround or adjustment I can make to avoid using these non-public symbols? Thank you in advance for your assistance.
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306
Dec ’24
App Rejected: Non-Public Symbols _lzma_code and _lzma_end in Payload/Hogs.app/Hogs
Hello, I have integrated LZMA2 compression into my iOS app, Hogs, and successfully implemented compression. However, when attempting to upload the app for TestFlight, I encountered an error: "The app references non-public symbols in Payload/Hogs.app/Hogs: _lzma_code, _lzma_end." These functions are part of the LZMA compression library (specifically LZMA2). Here's a detailed description of the issue: What I Have Done: LZMA2 Integration: I integrated LZMA2 compression into the app and created a wrapper around the LZMA functions (_lzma_code, _lzma_end) to prevent direct references. App Build Configuration: I ensured the LZMA2 library is linked correctly with the -lzma flag in the linker settings. I wrapped the LZMA functions in custom functions (my_lzma_code, my_lzma_end) in an attempt to avoid using the non-public symbols directly. Error Message: During the app submission process, I received the following error: "The app references non-public symbols in Payload/Hogs.app/Hogs: _lzma_code, _lzma_end." Steps Taken to Resolve: Checked if any LZMA functions were exposed incorrectly. Ensured that all non-public symbols were properly encapsulated in a wrapper. Verified linker settings to ensure the proper inclusion of the LZMA2 library. Request: Could anyone provide suggestions or best practices to resolve this issue and avoid references to non-public symbols? Should I use a different method for linking LZMA2 or encapsulating these symbols? Thank You: I appreciate your help in resolving this issue so I can move forward with submitting the app for TestFlight.
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371
Dec ’24
How do I locate and this Bundle Error
❌ Could not find email_ai.py in the app bundle. Available files: [] The error above is what I’m encountering. I’ve placed the referenced file both in the project directory and inside the app. However, every time I remove and reinsert the file into the folder within the app, it prompts me to designate the targets—I select all, but this doesn’t resolve the issue. I’m unsure how to properly reference the file so that it is recognised and included in the bundle. Any guidance would be greatly appreciated. this is my build phase: #!/bin/sh set -x # Prints each command before running it (for debugging) pwd # Shows the current working directory echo "$SRCROOT" # Shows what Xcode thinks is the project root ls -l "$SRCROOT/EmailAssistant/EmailAssistant/PythonScripts" # Lists files in the script folder export PYTHONPATH="/Users/caesar/.pyenv/versions/3.11.6/bin" /Users/caesar/.pyenv/versions/3.11.6/bin/python3 "$SRCROOT/EmailAssistant/EmailAssistant/PythonScripts/email_ai.py" echo "Script completed."
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461
Feb ’25
Passkey Creation SDK does not return Timeout Error on FaceID authentication times out.
We would like to show a user-friendly message but can not. Description: When attempting to create a duplicate passkey using the ASAuthrorizationController in iOS, the Face ID authentication times out SDK does not return a timeout specific error. Instead, it directly returns an error stating that duplicate passkey cannot be created. SDK to first handle the FaceID timeout case and provide a distinct timeout error so we can gracefully manage this scenario before the duplicate passkey validation occurs. Steps to Reproduce: Implement passkey creation flow using ASAuthorizationController. Attempt to register a duplicate passkey (e.g., using the same user ID and challenge). Let FaceID prompt timeout (do not interact with the authentication prompt).
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254
Dec ’24
Why Actor-isolated property cannot be passed 'inout' to 'async' function call?
Considering below dummy codes: @MainActor var globalNumber = 0 @MainActor func increase(_ number: inout Int) async { // some async code excluded number += 1 } class Dummy: @unchecked Sendable { @MainActor var number: Int { get { globalNumber } set { globalNumber = newValue } } @MainActor func change() async { await increase(&number) //Actor-isolated property 'number' cannot be passed 'inout' to 'async' function call } } I'm not really trying to make an increasing function like that, this is just an example to make everything happen. As for why number is a computed property, this is to trigger the actor-isolated condition (otherwise, if the property is stored and is a value type, this condition will not be triggered). Under these conditions, in function change(), I got the error: Actor-isolated property 'number' cannot be passed 'inout' to 'async' function call. My question is: Why Actor-isolated property cannot be passed 'inout' to 'async' function call? What is the purpose of this design? If this were allowed, what problems might it cause?
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394
Feb ’25
percentages
I want to know how to format doubles. In the program I have 4.3333 I just want to print 4 to the screen. I just want to print whole numbers. I'm using Swiftui with xcode. Please help. Thank you.
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275
Dec ’24
Trying to understand Swift-C++ interopability
Hi, I'm struggling to understand using Swift-C++ in the same project. I have an existing code-base that makes heavy use of Swift-Objective-C interoperability. We make use of swift classes in our project. When I enable swift-objective c interoperability I am running into numerous build errors in the generated bridging header. I'm trying to understand why these errors exist and what to do to get around them. I have a project that I've set up with some test code, and I'm running into an error here: public class Foo { let name: String public init(name: String) { self.name = name } } public class Bar { let name: String public init(name : String) { self.name = name; } public func getFoo() -> Foo { return Foo(name: self.name); } } In the header file: Unknown type name 'Foo' SWIFT_INLINE_THUNK Foo getFoo() SWIFT_SYMBOL("s:13ForestBuilder3BarC6getFooAA0E0CyF"); This error goes away if I use structs, but for the purposes of porting my codebase, I'd prefer to use classes. Do classes not play nice here? Or am I misunderstanding something. Thanks.
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435
Dec ’24
array
I'm using xcode 16.1 withSwift. I want to know how to call a function passing in an array. Also I need to know how to declare the function receiving the array. I currently have: func myfunc(costa: [Double]) { } I call it like this: myfunc(costa:[ ]) It's an array of Doubles. I don't get any errors but the array is always empty. Please help. Thank you.
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280
Dec ’24