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?
Post
Replies
Boosts
Views
Activity
On iOS 18 some string functions return incorrect values in some cases.
Found problems on replacingOccurrences() and split() functions, but there may be others.
In the results of these functions in some cases a character is left in the result string when it shouldn't.
This did not happen on iOS17 and older versions.
I created a very simple Test Project to reproduce the problem.
If I run these tests on iOS17 or older the tests succeed.
If I run these tests on iOS18 the tests fail.
test_TestStr1() function shows a problem in replacingOccurrences() directly using strings.
test_TestStr2() function shows a problem in split() that seems to happen only when bridging from NSString to String.
import XCTest
final class TestStrings18Tests: XCTestCase {
override func setUpWithError() throws {
// Put setup code here. This method is called before the invocation of each test method in the class.
}
override func tearDownWithError() throws {
// Put teardown code here. This method is called after the invocation of each test method in the class.
}
func test_TestStr1()
{
let str1 = "_%\u{7}1\u{7}_";
let str2 = "%\u{7}1\u{7}";
let str3 = "X";
let str4 = str1.replacingOccurrences(of: str2, with: str3);
//This should be true
XCTAssertTrue(str4 == "_X_");
}
func test_TestStr2()
{
let s1 = "TVAR(6)\u{11}201\"Ã\"\u{11}201\"A\"";
let s2 = s1.components(separatedBy: "\u{11}201");
let t1 = NSString("TVAR(6)\u{11}201\"Ã\"\u{11}201\"A\"") as String;
let t2 = t1.components(separatedBy: "\u{11}201");
XCTAssertTrue(s2.count == t2.count);
let c = s2.count
//This should be True
XCTAssertTrue(s2[0] == t2[0]);
}
}
Recently I updated to Xcode 14.0. I am building an iOS app to convert recorded audio into text. I got an exception while testing the application from the simulator(iOS 16.0).
[SpeechFramework] -[SFSpeechRecognitionTask handleSpeechRecognitionDidFailWithError:]_block_invoke Ignoring subsequent recongition error: Error Domain=kAFAssistantErrorDomain Code=1101 "(null)"
Error Domain=kAFAssistantErrorDomain Code=1107 "(null)"
I have to know what does the error code means and why this error occurred.
Does anyone know if there will be a Swift 6 version of "The Swift Programming Language" book and if so, when it will be released for Apple Books?
Hi I'm new here - I'm trying to learn Swift and SwiftUI.
Tried on PluralSight and Udemy but they have been outdated and thus hard to follow.
So after finding Apples own guides I felt relieved and happy, but now I'm stuck again.
After they've updated Xcode to use #Preview instead of PreviewProvider it's hard to follow along on their tutorial.
Does anyone know of good resources to study SwiftUI? Or know if apple plan to update their tutorials any time soon?
I'm here now if anyone's interested or it's useful information: https://developer.apple.com/tutorials/app-dev-training/managing-state-and-life-cycle
I've got a watch app, still with storyboard, WKInterfaceController and WatchConnectivity.
After updating it for swift 6 concurrency I thought I'd keep it for a little while without swift 6 concurrency dynamic runtime check.
So I added -disable-dynamic-actor-isolation in OTHER_SWIFT_FLAGS, but it doesn't seem to have an effect for the Apple Watch target. Without manually marking callbacks where needed with @Sendable in dynamic checks seem to be in place.
swiftc invocation is as (includes -disable-dynamic-actor-isolation):
swiftc -module-name GeoCameraWatchApp -Onone -enforce-exclusivity\=checked ... GeoCameraWatchApp.SwiftFileList -DDEBUG -enable-bridging-pch -disable-dynamic-actor-isolation -D DEBUG -enable-experimental-feature DebugDescriptionMacro -sdk /Applications/Xcode.app/Contents/Developer/Platforms/WatchOS.platform/Developer/SDKs/WatchOS11.2.sdk -target arm64_32-apple-watchos7.0 -g -module-cache-path /Users/stand/Library/Developer/Xcode/DerivedData/ModuleCache.noindex -Xfrontend -serialize-debugging-options -enable-testing -index-store-path /Users/stand/Library/Developer/Xcode/DerivedData/speedo-almhjmryctkitceaufvkvhkkfvdw/Index.noindex/DataStore -enable-experimental-feature OpaqueTypeErasure -Xcc -D_LIBCPP_HARDENING_MODE\=_LIBCPP_HARDENING_MODE_DEBUG -swift-version 6
...
-disable-dynamic-actor-isolation flag seems to be working for the iOS targets, I believe.
The flag is described here
Am I missing something? Should the flag work for both iOS and Apple Watch targets?
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?
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]?) -> 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
I have a class that I want to custom encode into JSON:
class Declination: Decodable, Encodable {
var asString: String
var asDouble: Double
init(_ asString: String) {
self.asString = asString
self.asDouble = raToDouble(asString)
}
required init(from decoder: Decoder) throws {
let value = try decoder.singleValueContainer()
self.asString = try value.decode(String.self)
self.asDouble = declinationToDouble(asString)
}
}
As you can see, I calculate the double form of the declination when I decode a JSON file containing the data. What I want to do now is ENCODE the class back out as a single string.
Currently the standard JSON encode in Swift produces the following:
"declination":{"asDouble":18.26388888888889,"asString":"+18:15:50.00"}
what I want to produce is:
declination:"+18:15:50.00"
How can I easily do that? I've read up about custom encoders and such, and I get confused about the containers and what keys are being used. I think there might be a simple answer where I could just code:
extension Coordinate: Encodable {
func encode(to encoder: Encoder) throws {
return encoder.encode(self.asString)
}
}
But experienced Swift developers will immediately see that won't work. Should I do JSONSerialization instead? Can I just write a toString() extension and have JSON pick that up?
Any help would be appreciated.
Thanks,
Robert
I’m working on a project in Xcode 16.2 and encountered an issue where getAPI() with a default implementation in a protocol extension doesn’t show up in autocomplete. Here’s a simplified version of the code:
import Foundation
public protocol Repository {
func getAPI(from url: String?)
}
extension Repository {
public func getAPI(from url: String? = "https://...") {
getAPI(from: url)
}
}
final class _Repository: Repository {
func getAPI(from url: String?) {
// Task...
}
}
let repo: Repository = _Repository()
repo.getAPI( // Autocomplete doesn't suggest getAPI()
I’ve tried the following without success:
• Clean build folder
• Restart Xcode
• Reindexing
Is there something wrong with the code, or is this a known issue with Xcode 16.2? I’d appreciate any insights or suggestions.
Hello, I have an issue with importing some .mp3 files into a swift playground project (in Xcode, not in the Playground app). They worked fine in the Xcode project, but for some reason playgrounds isn't able to find them. I imported them the exact same way as I did in the Xcode project.
The speaker mentions there is "less risk of creating a retain cycle in when capturing self in a closure within a value type", such as a SwiftUI view struct.
Can you elaborate on when this could actually occur?
Thanks!
Hey there-
I'm having a quite interesting bug on Swift Playgrounds.
I am trying to run my app with this following code snippet which does not compile on Swift Playgrounds, yet compiles on XCode (note: this is a Swift Playground app)
if #available(iOS 18.0, *) {
//simple function to get the indices of other items that have the same date as the "date" variable
let indices = data!.indices(where: { item in
let sameMonth = Calendar.current.component(.month, from: item.time) == Calendar.current.component(.month, from: date)
let sameYear = Calendar.current.component(.year, from: item.time) == Calendar.current.component(.year, from: date)
let sameDay = Calendar.current.component(.day, from: item.time) == Calendar.current.component(.year, from: date)
return sameDay && sameMonth && sameYear
})
However, the indices(where:) codeblock seems to stop the app from compiling (ONLY on Swift Playgrounds - it works perfectly fine on XCode).
I am getting the following error:
Cannot call value of non-function type 'Range<Array<Int>.Index>' (aka 'Range<Int>')
Please let me know if you have any insight regarding this issue.
-ColoredOwl
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?
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
}
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?
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
I am currently studying the Accelerate library by referring to Apple documentation.
Here is the link to the referenced document:
https://developer.apple.com/documentation/accelerate/veclib/vforce
When I executed the sample code provided at the bottom of the document, I found a case where the results were different.
let n = 10_000
let x = (0..<n).map { _ in
Float.random(in: 1 ... 10_000)
}
let y = x.map {
return sqrt($0)
}
and
let y = [Float](unsafeUninitializedCapacity: n) { buffer, initializedCount in
vForce.sqrt(x,
result: &buffer)
initializedCount = n
}
The code below is provided to observe the issue described above.
import Accelerate
Task {
let n = 1//10_000
let x = (0..<n).map { _ in
Float(6737.015)//Float.random(in: 1 ... 10_000)
}
let y = x.map {
return sqrt($0)
}
try? await Task.sleep(nanoseconds: 1_000_000_000)
let z = [Float](unsafeUninitializedCapacity: n) { buffer, initializedCount in
vForce.sqrt(x, result: &buffer)
initializedCount = n
}
}
For a value of 6737.015 when calculating the square root:
Using the sqrt(_:) function gives the result 82.07932,
While using the vForce.sqrt(_:result:) function gives the result 82.07933.
Using a calculator, the value comes out as 82.07932139, which shows that the result from vForce is incorrect.
Could you explain the reason behind this difference?
Hey everyone,
I’m learning async/await and trying to fetch an image from a URL off the main thread to avoid overloading it, while updating the UI afterward. Before starting the fetch, I want to show a loading indicator (UI-related work). I’ve implemented this in two different ways using Task and Task.detached, and I have some doubts:
Is using Task { @MainActor the better approach?
I added @MainActor because, after await, the resumed execution might not return to the Task's original actor. Is this the right way to ensure UI updates are done safely?
Does calling fetchImage() on @MainActor force it to run entirely on the main thread?
I used an async data fetch function (not explicitly marked with any actor). If I were to use a completion handler instead, would the function run on the main thread?
Is using Task.detached overkill here?
I tried Task.detached to ensure the fetch runs on a non-main actor. However, it seems to involve unnecessary actor hopping since I still need to hop back to the main actor for UI updates. Is there any scenario where Task.detached would be a better fit?
class ViewController : UIViewController{
override func viewDidLoad() {
super.viewDidLoad()
//MARK: First approch
Task{@MainActor in
showLoading()
let image = try? await fetchImage() //Will the image fetch happen on main thread?
updateImageView(image:image)
hideLoading()
}
//MARK: 2nd approch
Task{@MainActor in
showLoading()
let detachedTask = Task.detached{
try await self.fetchImage()
}
updateImageView(image:try? await detachedTask.value)
hideLoading()
}
}
func fetchImage() async throws -> UIImage {
let url = URL(string: "https://via.placeholder.com/600x400.png?text=Example+Image")!
//Async data function call
let (data, response) = try await URLSession.shared.data(from: url)
guard let httpResponse = response as? HTTPURLResponse, httpResponse.statusCode == 200 else {
throw URLError(.badServerResponse)
}
guard let image = UIImage(data: data) else {
throw URLError(.cannotDecodeContentData)
}
return image
}
func showLoading(){
//Show Loader handling
}
func hideLoading(){
//Hides the loader
}
func updateImageView(image:UIImage?){
//Image view updated
}
}
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