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array.contains(where: ...) returns true in debugger console, but false in application
I am encountering a strange issue. I have a class that manages a selection of generic items T in an Array. It's a work in progress, but I'l try to give a gist of the setup. class FileManagerItemModel: NSObject, Identifiable, Codable, NSCopying, Transferable, NSItemProviderReading, NSItemProviderWriting { var id: URL static func == (lhs: FileManagerItemModel, rhs: FileManagerItemModel) -> Bool { lhs.fileURL == rhs.fileURL } var fileURL: URL { FileManagerItemModel.normalizedFileURL(type: type, rootURL: rootURL, filePath: filePath) } init(type: FileManagerItemType, rootURL: URL, fileURL: URL) { self.type = type self.rootURL = rootURL self.filePath = FileManagerItemModel.filePathRelativeToRootURL(fileURL: fileURL, rootURL: rootURL) ?? "[unknown]" self.id = FileManagerItemModel.normalizedFileURL(type: type, rootURL: rootURL, filePath: filePath) } } The class that manages the selection of these FileManagerItemModels is like so: @Observable class MultiSelectDragDropCoordinator<T: Hashable>: ObservableObject, CustomDebugStringConvertible { private(set) var multiSelectedItems: [T] = [] func addToSelection(_ item: T) { if !multiSelectedItems.contains(where: { $0 == item }) { multiSelectedItems.append(item) } } ... } My issue is that the check if !multiSelectedItems.contains(where: { $0 == item }) in func addToSelection fails. The if is always executed, even if multiSelectedItems contains the given item. Now, my first thought would be to suspect the static func == check. But that check works fine and does what it should do. Equality is defined by the whole fileURL. So, the if should have worked. And If I put a breakpoint in func addToSelection on the if, and type po multiSelectedItems.contains(where: { $0 == item }) in the debug console, it actually returns true if the item is in multiSelectedItems. And it properly return false if the item is not in multiSelectedItems. Still, if I then continue stepping through the app after the breakpoint was hit and I confirmed that the contains should return true, the app still goes into the if, and adds a duplicate item. I tried assigning to a variable, I tried using a function and returning the true/false. Nothing helps. Does anyone have an idea on why the debugger shows one (the correct and expected) thing but the actual code still does something different?
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546
Feb ’25
SwiftUI Entry Point - Proper Location In Project
Hi In C#, one can define associated functions by the following. Notice that "Declarations DE" is a reference to a function in another C# project file. This lets the compiler know that there are other references in the project. Likewise, "Form_Load" is the entry point of the code, similar to "main" in C. Any calls to related functions can be made in this section, to the functions that have been previously defined above. So I set out trying to find similar information about SwiftUI, and found several, but only offer partial answers to my questions. The YouTube video... Extracting functions and subviews in SwiftUI | Bootcamp #20 - YouTube ... goes into some of the details, but still leaves me hanging. Likewise... SOLVED: Swift Functions In Swift UI – SwiftUI – Hacking with Swift forums ... has further information, but nothing concrete that I am looking for. Now in the SwiftUI project, I tried this... The most confusing thing for me, is where is "main"? I found several examples that call functions from the structure shown above, BUT I have no reason as to why. So one web example on StackOverFlow called the function from position 1. That did not work. Position 2 worked to call the function at position 3, but really, why? All this activity brings up a lot of questions for me, such as: Does SwiftUI need function callouts similar to C#, and they are called out even before running "main". I seem to recall Borland Delphi being this way as well. How does SwiftUI make references to other classes (places where other functions are stored in separate files)? Does SwiftUI actually make use of "main" in the normal sense, i.e. similar to C, C#, Rust and so on? I did notice that once a SwiftUI function is called, it makes reference to data being passed very similar to other languages, at least for the examples I found. Note that I looked at official SwiftUI documentation, but did not come across information that answers the above.
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533
Dec ’24
NSDictionary.isEqual(to:) with Swift dictionary compiles on macOS but not on iOS
The following code works when compiling for macOS: print(NSMutableDictionary().isEqual(to: NSMutableDictionary())) but produces a compiler error when compiling for iOS: 'NSMutableDictionary' is not convertible to '[AnyHashable : Any]' NSDictionary.isEqual(to:) has the same signature on macOS and iOS. Why does this happen? Can I use NSDictionary.isEqual(_:) instead?
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484
Feb ’25
cell.textLabel?.text breaking if a number value is in an array
Hi the below array and code to output a list item works fine: var quotes = [ [ "quote": "I live you the more ...", "order": "1" ], [ "quote": "There is nothing permanent ...", "order": "2" ], [ "quote": "You cannot shake hands ...", "order": "3" ], [ "quote": "Lord, make me an instrument...", "order": "4" ] ] cell.textLabel?.text = quotes[indexPath.row]["quote"] However if I change the "order" values to be numbers rather than text like below then for the above line I get an error message in Xcode "No exact matches in call to subscript". Please could someone tell me how to make it work with the numbers stored as numbers? (I'm wondering if creating an any array type and using the .text function has caused a conflict but I can't find how to resolve) [ "quote": "I live you the more ...", "order": 1 ], [ "quote": "There is nothing permanent ...", "order": 2 ], [ "quote": "You cannot shake hands ...", "order": 3 ], [ "quote": "Lord, make me an instrument...", "order": 4 ] ] Thank you for any pointers :-)
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437
Feb ’25
Bridging Headers is unsupported or Module compiled with Swift 5.5.1 cannot be imported by the Swift 5.6 complier
Hello guys! I faced a problem with building... My device suddenly updated to iOS 15.4.1, my Xcode was 13.2 and I had to update it to the latest version (13.3.1) to build the app. After the update, I had a few problems which were successfully solved but one of them stopped me for a few hours. The problem is with Bridging Headers or Swift Compiler, I really don't know what I did badly, and what causes problems. On several forums I often read that is important to set: Build Settings &gt; Build Options &gt; Build Libraries for Distribution But in any case it doesn't work, on yes: error: using bridging headers with module interfaces is unsupported on no: (line with import framework SWXMLHash) /Users/blablabla/SSLModel.swift:9:8: error: module compiled with Swift 5.5.1 cannot be imported by the Swift 5.6 compiler: /Users/blablabla2/Build/Products/Debug-iphoneos/SWXMLHash.framework/Modules/SWXMLHash.swiftmodule/arm64-apple-ios.swiftmodule import SWXMLHash It will be important that I use Carthage. What should I do? Clone all 10 frameworks that I use and re-build them with a new Xcode which includes compiler 5.6? That may be a bad solution... Any answers on similar topics don't help..
3
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2.9k
Jul ’25
Hash Collision in Data type
I notice that Swift Data type's hashValue collision when first 80 byte of data and data length are same because of the Implementation only use first 80 bytes to compute the hash. https://web.archive.org/web/20120605052030/https://opensource.apple.com/source/CF/CF-635.21/CFData.c also, even if hash collision on the situation like this, I can check data is really equal or not by == does there any reason for this implementation(only use 80 byte of data to make hashValue)? test code is under below let dataArray: [UInt8] = [ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 ] var dataArray1: [UInt8] = dataArray var dataArray2: [UInt8] = dataArray dataArray1.append(contentsOf: [0x00, 0x00, 0x00, 0x00]) dataArray2.append(contentsOf: [0xff, 0xff, 0xff, 0xff]) let data1 = Data(dataArray1) let data2 = Data(dataArray2) // Only last 4 byte differs print(data1.hashValue) print(data2.hashValue) print(data1.hashValue == data2.hashValue) // true print(data1 == data2) // false
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564
Feb ’25
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?
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1.1k
Dec ’24
Implementing RawRepresentable for a DictionaryType has broken my Test target build. Not sure how to fix things...
For my app I've created a Dictionary that I want to persist using AppStorage In order to be able to do this, I added RawRepresentable conformance for my specific type of Dictionary. (see code below) typealias ScriptPickers = [Language: Bool] extension ScriptPickers: @retroactive RawRepresentable where Key == Language, Value == Bool { public init?(rawValue: String) { guard let data = rawValue.data(using: .utf8), let result = try? JSONDecoder().decode(ScriptPickers.self, from: data) else { return nil } self = result } public var rawValue: String { guard let data = try? JSONEncoder().encode(self), // data is Data type let result = String(data: data, encoding: .utf8) // coerce NSData to String else { return "{}" // empty Dictionary represented as String } return result } } public enum Language: String, Codable, { case en = "en" case fr = "fr" case ja = "ja" case ko = "ko" case hr = "hr" case de = "de" } This all works fine in my app, however trying to run any tests, the build fails with the following: Conflicting conformance of 'Dictionary<Key, Value>' to protocol 'RawRepresentable'; there cannot be more than one conformance, even with different conditional bounds But then when I comment out my RawRepresentable implementation, I get the following error when attempting to run tests: Value of type 'ScriptPickers' (aka 'Dictionary<Language, Bool>') has no member 'rawValue' I hope Joseph Heller is out there somewhere chuckling at my predicament any/all ideas greatly appreciated
1
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554
Feb ’25
Swift 6 crash calling requestAutomaticPassPresentationSuppression
I found a similar problem here https://developer.apple.com/forums/thread/764777 and I could solve my problem by wrapping the call to requestAutomaticPassPresentationSuppression in a call to DispatchQueue.global().async. But my question is if this is really how things should work. Even with strict concurrency warnings in Swift 6 I don't get any warnings. Just a runtime crash. How are we supposed to find these problems? Couldn't the compiler assist with a warning/error. Why does the compiler make the assumptions it does about the method that is declared like this: @available(iOS 9.0, *) open class func requestAutomaticPassPresentationSuppression(responseHandler: @escaping (PKAutomaticPassPresentationSuppressionResult) -> Void) -> PKSuppressionRequestToken Now that we have migrated to Swift 6 our code base contains a bunch of unknown places where it will crash as above.
2
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473
Feb ’25
SwiftData and 'NSKeyedUnarchiveFromData' should not be used to for un-archiving and will be removed in a future release
I get this red warning in Xcode every time my app is syncing to the iCloud. My model has only basic types and enum that conform to Codable so i'm not sure what is the problem. App is working well, synchronization works. But the warning doesn't look good. Maybe someone has idea how to debug it.
2
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901
Dec ’24
Dateformatter returns date in incorrect format
I have configured DateFormatter in the following way: let df = DateFormatter() df.dateFormat = "yyyy-MM-dd'T'HH:mm:ss'Z'" df.locale = .init(identifier: "en") df.timeZone = .init(secondsFromGMT: 0) in some user devices instead of ISO8601 style it returns date like 09/25/2024 12:00:34 Tried to change date format from settings, changed calendar and I think that checked everything that can cause the problem, but nothing helped to reproduce this issue, but actually this issue exists and consumers complain about not working date picker. Is there any information what can cause such problem? May be there is some bug in iOS itself?
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424
Feb ’25
Possible typo in concurrency diagram (WWDC25: Elevate an app with Swift concurrency)
Hello, While watching WWDC25: Code-along: Elevate an app with Swift concurrency at timestamp 25:48, I noticed something in the slide/diagram that might be incorrect. The diagram shows ExtractSticker twice, but based on the code context and spoken explanation, I think it was meant to be ExtractSticker and ExtractColor. Reasoning: The surrounding code and narration describe the use of async let and a Sendable Data object. From the flow, one task extracts a sticker while the other extracts a color, so it seems like the diagram is inconsistent. I do understand that with @concurrent, having two ExtractSticker operations on the same Data is technically possible (with two concurrent process executing their respective ExtractSticker) — but that would be a different meaning than what the talk was describing. Since concurrency is already a subtle and error-prone topic, I thought it was worth pointing this out. If I’m mistaken, I’d love clarification. Otherwise, this could be a small correction to keep things aligned and clearer for everyone. Minor point overall, but Swift 6’s concurrency model is doing a fantastic job at helping us write safer code—so thank you to the team for that! (Attaching screenshots for reference)
2
0
1.8k
Aug ’25
NSPredicate return wrong result
NSPredicate(format: "SELF MATCHES %@", "^[0-9A-Z]+$").evaluate(with: "126𝒥ℰℬℬ𝒢𝒦𝒮33") Returns true, and I don't know why. 𝒥ℰℬℬ𝒢𝒦𝒮 is not between 0-9 and A-Z, and why it returns true? How to avoid similar problem like this when using NSPredicate?
2
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543
Feb ’25
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
974
Dec ’24
Common blocks in Swift?
I am porting an old app from ObjC. The app uses many defined constants such as: #define COM_OFFSET 12.5 and many variables that are read and/or written throughout the App, such as: PCDate* Dates[367]; @class PCMainView; PCMainView* MainView; in one file called "PCCommon.h" How do I duplicate this function in Swift? I have looked around and have found no help. Thanks in advance.
1
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447
Dec ’24
How to convert a function into a variable?
Hello, I have a test variable here which works fine: var quotes: [(quote: String, order: Int)] = [ ("I live you the more ...", 1), ("There is nothing permanent ...", 2), ("You cannot shake hands ...", 3), ("Lord, make me an instrument...", 4) ] and I have a test function which successfully pulls data from a mysql database via a web service and displays it via the "print" function: func getPrice(){ 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 print(row["quote"]!) print(row["order"]!) } } else{ } } else{ print("wrong :-(") } }.resume() } } Please can you tell me how to re-write the quotes variable/array so that it returns the results that are found in the getPrice() function?
3
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448
Mar ’25
App sometimes crashes when inserting String into Set with assertion ELEMENT_TYPE_OF_SET_VIOLATES_HASHABLE_REQUIREMENTS
Xcode downloaded a crash report for my app that crashed when trying to insert a String into a Set<String>. Apparently there was an assertion failure ELEMENT_TYPE_OF_SET_VIOLATES_HASHABLE_REQUIREMENTS. I assume that this assertion failure happened because the hash of the new element didn't match the hash of an equal already inserted element, but regardless, I don't understand how inserting a simple string could trigger this assertion. Here is essentially the code that leads to the crash. path is any file system directory, and basePath is a directory higher in the hierarchy, or path itself. var scanErrorPaths = Set<String>() func main() { let path = "/path/to/directory" let basePath = "/path" let fileDescriptor = open(path, O_RDONLY) if fileDescriptor < 0 { if (try? URL(fileURLWithPath: path, isDirectory: false).checkResourceIsReachable()) == true { scanErrorPaths.insert(path.relativePath(from: basePath)!) return } } extension String { func relativePath(from basePath: String) -> String? { if basePath == "" { return self } guard let index = range(of: basePath, options: .anchored)?.upperBound else { return nil } return if index == endIndex || basePath == "/" { String(self[index...]) } else if let index = self[index...].range(of: "/", options: .anchored)?.upperBound { String(self[index...]) } else { nil } } } crash.crash
7
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761
3w
Attrubute can only be applied to types not declarations
Error: "Attrubute can only be applied to types not declarations" on line 2 : @unchecked @unchecked enum ReminderRow : Hashable, Sendable { case date case notes case time case title var imageName : String? { switch self { case .date: return "calendar.circle" case .notes: return "square.and.pencil" case .time: return "clock" default : return nil } } var image : UIImage? { guard let imageName else { return nil } let configuration = UIImage.SymbolConfiguration(textStyle: .headline) return UIImage(systemName: imageName, withConfiguration: configuration) } var textStyle : UIFont.TextStyle { switch self { case .title : return .headline default : return .subheadline } } }
1
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279
3w
How to create an array using a loop
Hello, Please can you tell me how to create an array of dictionaries? This code below should create 4 dictionaries in an array, but I'm getting these errors: For line "var output = [id: "testID", name: "testName"]": cannot find 'name' in scope Type '(any AnyObject).Type' cannot conform to 'Hashable' For line "return output": Type '(any AnyObject).Type' cannot conform to 'Hashable' var quotes: [(id: String, name: String)] { var output = [[(id: String, name: String)]] () for i in 1...4 { var output = [id: "testID", name: "testName"] } return output }
2
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367
Mar ’25
Basic c++xcodeproj call to swift code
I have c++ macOs app(Xcode +14) and I try to add call to swift code. I can't find any simple c++ xcodeproj call to swift code. I create new simple project and fail to build it with error when I try to include #include <SwiftMixTester/SwiftMixTester-Swift.h>: main.m:9:10: error: 'SwiftMixTester/SwiftMixTester-Swift.h' file not found (in target 'CppCallSwift' from project 'CppCallSwift') note: Did not find header 'SwiftMixTester-Swift.h' in framework 'SwiftMixTester' (loaded from '/Users/yanivsmacm4/Library/Developer/Xcode/DerivedData/CppCallSwift-exdxjvwdcczqntbkksebulvfdolq/Build/Products/Debug') . Please help.
5
0
384
2w