I have a transformation function that takes in data, executes some instructions, and returns an output. This function is dynamic and not shipped with the binary. Currently, I’m executing it using JavaScriptCore.JSContext, which works well, but the function itself is written in JavaScript.
Is there a way to achieve something similar using Swift – such as executing a dynamic Swift script, either directly or through other means? I know this is possible on macOS, but I’m not sure about iOS. I’ve also heard that extensions might open up some possibilities here. Any insights or alternative approaches would be appreciated.
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谁能告诉我为什么?
“[正在运行] swift ”d:\vscode object\swift object\ceshi.swift”
JIT 会话错误:未找到符号:[ $ss 27_allocateUninitializedArrayySayxG_BptBwlFyp_Tg5 ]
未能具体化符号: { (main, { main, $sSa 12_endMutationyyF, $ss 5print_9separator10terminatoryypd_S2StFfA0_, $ss 5print_9separator10terminatoryypd_S2StFfA1_, $ss 27_finalizeUninitializedArrayySayxGABnlF }) }
[完成] 在 0.47 秒内退出并带有 code=4294967295”
当“Swift for Windows”在 VSCode for Windows 上运行时。
路径为 true,“Package-swift-lsp: Path”为 true。
谁能告诉我为什么?
Topic:
Programming Languages
SubTopic:
Swift
Module compiled with Swift 6.0.3 cannot be imported by the Swift 6.1 compiler: /private/var/tmp/_bazel_xx/8b7c61ad484d9da1bf94a11f12ae6ffd/rules_xcodeproj.noindex/build_output_base/execroot/main/CustomModules/BIYThred/CocoaLumberjack/framework/CocoaLumberjack.framework/Modules/CocoaLumberjack.swiftmodule/arm64-apple-ios.swiftmodule
Hello dear community,
I have the sample code from Apple “CapturingDepthUsingLiDAR” to access the LiDAR on my iPhone 12 Pro. My goal is to use the “photo output” function to generate a point cloud from a single image and then save it as a ply file. So far I have tested different approaches to create a .ply file from the depthmap, the intrinsic camera data and the rgba values. Unfortunately, I have had no success so far and the result has always been an incorrect point cloud.
My question now is whether there are already approaches to this and whether anyone has any experience with it.
Thank you very much in advance!!!
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
}
Topic:
Programming Languages
SubTopic:
Swift
I'm having trouble dealing with concurrency with the SFAuthorizationPluginView. Does anybody know how this can be solved?
https://developer.apple.com/documentation/securityinterface/sfauthorizationpluginview
The crux of it is:
If I inherit an object as part of an API, and the API is preconcurrency, and thus is nonisolated (but in reality is @MainActor), how do I return a @MainActor GUI element?
https://developer.apple.com/documentation/securityinterface/sfauthorizationpluginview/firstresponder()
The longer story:
I made my view class inherit SFAuthorizationPluginView.
The API is preconcurrency (but not marked as preconcurrency)
I started using concurrency in my plugin to retrieve data over XPC. (https://developer.apple.com/documentation/xpc/xpcsession + https://developer.apple.com/documentation/swift/withcheckedthrowingcontinuation(isolation:function:_:))
Once I retrieve the data over XPC, I need to post it on GUI, hence I've set my view class as @MainActor in order to do the thread switch.
Swift compiler keeps complaining:
override func firstResponder() -> NSResponder? {
return usernameField
}
"Main actor-isolated property 'usernameField' can not be referenced from a nonisolated context; this is an error in the Swift 6 language mode"
override func firstResponder() -> NSResponder? {
MainActor.assumeIsolated {
return usernameField
}
}
"Sending 'self' risks causing data races; this is an error in the Swift 6 language mode"
I think fundamentally, the API is forcing me to give away a @MainActor variable through a nonisolated function, and there is no way to shut up the compiler.
I've tried @preconcurrency and it has no effect as far as I can tell. I've also tried marking the function explicitly as nonisolated.
The rest of the API are less problematic, but returning a GUI variable is exceptionally difficult.
Hello,
It is mentioned in CryptoTokenKit documentation:
You use the CryptoTokenKit framework to easily access cryptographic tokens. Tokens are physical devices built in to the system, located on attached hardware (like a smart card), or accessible through a network connection.
However, it looks like there is lack of documentation with simple example, how to access network token.
I have a certificates in HSM (hardware secure module), which is accessible on network, and I'd like to access certificates on HSM on my Mac.
Does anybody know, where to start with implementation?
Thank you.
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?
Topic:
Programming Languages
SubTopic:
Swift
I'm developing an audio unit for use on iOS. The AUv3 worked fine with xcode 15.X and swift 5.X. I recently tried to submit an update to my plug-in but Apple refused submission because my Xcode was not the latest. Now that I'm on Xcode 16.4 I can't get my project to compile, even when following all of the same previous steps.
As one example of a change, Xcode doesn't appear to include the “C++ and Objective-C interoperability” build setting that it used to. This setting is noted in the Swift documentation and I used to need it, https://www.swift.org/documentation/cxx-interop/project-build-setup/#mixing-swift-and-c-using-xcode
Currently my C++ code can't see anything from Swift, and I get a "Use of undeclared identifier 'project_name'". I've selected Switch support for version 5.0 in an attempt to minimize changes from Apple.
My process is I generate an Xcode project file from my audio plugin support, JUCE. Then I add in the swift files, click yes to create bridging headers, but c++ doesn't see swift anymore. I'd greatly appreciate any suggestions.
Topic:
Programming Languages
SubTopic:
Swift
I'm struggling to convert Swift 5 to Swift 6.
As advised in doc, I first turned strict concurrency ON. I got no error.
Then, selected swift6… and problems pop up.
I have a UIViewController with
IBOutlets: eg a TextField.
computed var eg duree
func using UNNotification: func userNotificationCenter
I get the following error in the declaration line of the func userNotificationCenter:
Main actor-isolated instance method 'userNotificationCenter(_:didReceive:withCompletionHandler:)' cannot be used to satisfy nonisolated requirement from protocol 'UNUserNotificationCenterDelegate'
So, I declared the func as non isolated.
This func calls another func func2, which I had also to declare non isolated.
Then I get error on the computed var used in func2
Main actor-isolated property 'duree' can not be referenced from a nonisolated context
So I declared duree as nonsilated(unsafe).
Now comes the tricky part.
The computed var references the IBOutlet dureeField
if dureeField.text == "X"
leading to the error
Main actor-isolated property 'dureeField' can not be referenced from a nonisolated context
So I finally declared the class as mainActor and the textField as nonisolated
@IBOutlet nonisolated(unsafe) weak var dureeField : UITextField!
That silences the error (but declaring unsafe means I get no extra robustness with swift6) just to create a new one when calling dureeField.text:
Main actor-isolated property 'text' can not be referenced from a nonisolated context
Question: how to address properties inside IBOutlets ? I do not see how to declare them non isolated and having to do it on each property of each IBOutlet would be impracticable.
The following did work, but will make code very verbose:
if MainActor.assumeIsolated({dureeField.text == "X"}) {
So I must be missing something.
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
}
}
Consider this simple miniature of my iOS Share Extension:
import SwiftUI
import Photos
class ShareViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
if let itemProviders = (extensionContext?.inputItems.first as? NSExtensionItem)?.attachments {
let hostingView = UIHostingController(rootView: ShareView(extensionContext: extensionContext, itemProviders: itemProviders))
hostingView.view.frame = view.frame
view.addSubview(hostingView.view)
}
}
}
struct ShareView: View {
var extensionContext: NSExtensionContext?
var itemProviders: [NSItemProvider]
var body: some View {
VStack{}
.task{
await extractItems()
}
}
func extractItems() async {
guard let itemProvider = itemProviders.first else { return }
guard itemProvider.hasItemConformingToTypeIdentifier(UTType.url.identifier) else { return }
do {
guard let url = try await itemProvider.loadItem(forTypeIdentifier: UTType.url.identifier) as? URL else { return }
try await downloadAndSaveMedia(reelURL: url.absoluteString)
extensionContext?.completeRequest(returningItems: [])
}
catch {}
}
}
On the line 34
guard let url = try await itemProvider.loadItem
...
I get these warnings:
Passing argument of non-sendable type '[AnyHashable : Any]?' outside of main actor-isolated context may introduce data races; this is an error in the Swift 6 language mode
1.1. Generic enum 'Optional' does not conform to the 'Sendable' protocol (Swift.Optional)
Passing argument of non-sendable type 'NSItemProvider' outside of main actor-isolated context may introduce data races; this is an error in the Swift 6 language mode
2.2. Class 'NSItemProvider' does not conform to the 'Sendable' protocol (Foundation.NSItemProvider)
How to fix them in Xcode 16?
Please provide a solution which works, and not the one which might (meaning you run the same code in Xcode, add your solution and see no warnings).
I tried
Decorating everything with @MainActors
Using @MainActor in the .task
@preconcurrency import
Decorating everything with @preconcurrency
Playing around with nonisolated
Is this possible while inserting a String into Set
Crashed: com.apple.root.user-initiated-qos.cooperative
0 libswiftCore.dylib 0xf4c0 _assertionFailure(_:_:flags:) + 136
1 libswiftCore.dylib 0x17f484 ELEMENT_TYPE_OF_SET_VIOLATES_HASHABLE_REQUIREMENTS(_:) + 3792
2 MyEatApp 0x44f6e8 specialized _NativeSet.insertNew(_:at:isUnique:) + 4333926120 (<compiler-generated>:4333926120)
3 MyEatApp 0x44eaec specialized Set._Variant.insert(_:) + 4333923052 (<compiler-generated>:4333923052)
4 MyEatApp 0x479f7c HomeViewModel.hanldeAnnouncementCard(from:) + 293 (HomeViewModel+PersonalizedOffer.swift:293)
5 libswift_Concurrency.dylib 0x5c134 swift::runJobInEstablishedExecutorContext(swift::Job*) + 292
6 libswift_Concurrency.dylib 0x5d5c8 swift_job_runImpl(swift::Job*, swift::SerialExecutorRef) + 156
7 libdispatch.dylib 0x13db0 _dispatch_root_queue_drain + 364
8 libdispatch.dylib 0x1454c _dispatch_worker_thread2 + 156
9 libsystem_pthread.dylib 0x9d0 _pthread_wqthread + 232
10 libsystem_pthread.dylib 0xaac start_wqthread + 8
func oneStepForward(_ input: Int) -> Int {
return input + 1
}
func oneStepBackward(_ input: Int) -> Int {
return input - 1
}
func chooseStepFunction(backward: Bool) -> (Int) -> Int {
return backward ? oneStepBackward : oneStepForward
//Error. type of expression is ambiguous without a type annotation
}
Why am I getting this error ?
If I change this function to the following it works and will compile.
func chooseStepFunction(backward: Bool) -> (Int) -> Int {
if backward {
return oneStepBackward
} else {
return oneStepForward
}
}
// Why am I getting the error in the previous version while it works in the second version ?
Thx in advance.
I'm using Network Framework to transfer files between 2 devices. The "secondary" device sends file requests to the "primary" device, and the primary sends the files back.
When the primary gets the request, it responds like this:
do {
let data = try Data(contentsOf: filePath)
let priSecDataFilePacket = PriSecDataFilePacket(fileName: filename, dataBlob: data)
let jsonData = try JSONEncoder().encode(priSecDataFilePacket)
let message = NWProtocolFramer.Message(priSecMessageType: PriSecMessageType.priToSecDataFile)
let context = NWConnection.ContentContext(identifier: "TransferUtility", metadata: [message])
connection.send(content: encodedJsonToSend, contentContext: context, isComplete: true, completion: .idempotent)
} catch {
print("\(error)")
}
It works great, even for hundreds of file requests. The problem arises if some files being requested are extremely large, like 600MB. You can see the memory speedometer on the primary quickly ramp up to the yellow zone, at which point iOS kills the app for high memory use, and you see the Jetsam log.
I changed the code to skip JSON encoding the binary file as a test, and that helped a bit, but it still goes too high; the real offender is the step where it loads the 600MB file into the data var:
let data = try Data(contentsOf: filePath)
If I remark out everything else and just leave that one line, I can still see the memory use spike.
As a fix, I'm rewriting this so the secondary requests the file in 5MB chunks by telling the primary a byte range such as "0-5242880" or "5242881-10485760", and then reassembling the chunks on the secondary once they all come in. So far this seems promising, but it's a fair amount of work.
My question: Does Network Framework have a built-in way to stream those bytes straight from disk as it sends them? So that I could send all the data in one single request without having to load the bytes into memory?
I filed the following issue on swiftlang/swift on GitHub (Aug 8th), and a followup the swift.org forums, but not getting any replies. As we near the release of Swift 6.2, I want to know if what I'm seeing below is expected, or if it's another case where the compiler needs a fix.
protocol P1: Equatable { }
struct S1: P1 { }
// Error: Conformance of 'S1' to protocol 'P1' crosses into main actor-isolated code an can cause data races
struct S1Workaround: @MainActor P1 { } // OK
// Another potential workaround if `Equatable` conformance can be moved to the conforming type.
protocol P2 { }
struct S2: Equatable, P2 { } // OK
There was a prior compiler bug fix which addressed inhereted protocols regarding @MainActor. For Equatable, one still has to use @MainActoreven when the default actor isolation is MainActor.
Also affects Hashable and any other protocol inheriting from Equatable.
AsyncStream { continuation in
Task {
let response = await getResponse()
continuation.yield(response)
continuation.finish()
}
}
In this WWDC video https://developer.apple.com/videos/play/wwdc2025/231/ at 8:20 the presenter mentions that if the "Task gets cancelled, the Task inside the function will automatically get cancelled too". The documentation does not mention anything like this.
From my own testing on iOS 18.5, this is not true.
I came across a code
let myFruitBasket = ["apple":"red", "banana": "yellow", "budbeeri": "dark voilet", "chikoo": "brown"]
Can we have range for keys and values of dictionary, it will be convenient
for keys
print(myFruitBasket.keys[1...3])
// banana, budbeeri, chikoo
same for values
print(myFruitsBasket.values[1...3])
// yellow, voilet, brown
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!))
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
}
}
}
}
Topic:
Programming Languages
SubTopic:
Swift