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!!!
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I get many warnings like this when I build an old project.
I asked AI chatbot which gave me several solutions, the recommended one is:
var hashBag = [String: Int]()
func updateHashBag() async {
var tempHashBag = hashBag // make copy
await withTaskGroup(of: Void.self) { group in
group.addTask {
tempHashBag["key1"] = 1
}
group.addTask {
tempHashBag["key2"] = 2
}
}
hashBag = tempHashBag // copy back?
}
My understanding is that in the task group, the concurrency engine ensures synchronized modifications on the temp copy in multiple tasks. I should not worry about this.
My question is about performance.
What if I want to put a lot of data into the bag? Does the compiler do some kind of magics to optimize low level memory allocations? For example, the temp copy actually is not a real copy, it is a special reference to the original hash bag; it is only grammar glue that I am modifying the copy.
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
Hello
I want to implement customisation to swift argumentparser, Here are following changes want to do it in my cli
changing default footer present in help command output
currently help command output coming like this
OVERVIEW: clisample
USAGE: clisample <subcommand>
OPTIONS:
--version show the version.
-h, --help show the help.
SUBCOMMANDS:
logs (default) Export logs for clisample processes.
See 'clisample --help' for more information.'
so instead of
See 'clisample --help' for more information.'
I want my own string
For more details, run 'clisample help <subcommand>'
customise error string getting from validation error
Error: Missing value for '-t <time>'
Help: -t <time> Time window (e.g. 10h, 30m, 2d).
Usage: clisample logs --time <time>
See 'clisample logs --help' for more information.
so I want error output with example and customised footer, like this
Error: Missing value for '-t <time>'
Help: -t <time> Time window (e.g. 10h, 30m, 2d).
Usage: clisample logs --time <time>
Example: clisample logs -t 5m
For more details, run 'clisample help <subcommand>'
Is this changes possible from anyway?
I want to load images from my bundle, which works fine when running the main app. However this does not work when running UI Tests. I read that the test bundle is not the main bundle when running tests. I try loading the bundle via this snippet:
let bundle = Bundle(for: Frames_HoerspielUITests.self)
This is my test class wrapped these the canImport statements so it can be added to the main app target and used for getting the correct bundle:
#if canImport(XCTest)
import XCTest
final class Frames_HoerspielUITests: XCTestCase {
override func setUpWithError() throws {
continueAfterFailure = false
}
override func tearDownWithError() throws { }
@MainActor
func testExample() throws {
let app = XCUIApplication()
app.launch()
}
@MainActor
func testLaunchPerformance() throws {
measure(metrics: [XCTApplicationLaunchMetric()]) {
XCUIApplication().launch()
}
}
}
#else
final class Frames_HoerspielUITests { }
#endif
However while this works when running the main app, it still fails in the UI tests. It is a SwiftUI only app. and I can't add the images to the asset catalog because they are referenced from another location.
Any ideas? Thank you
Hi,
I have a complex structure of classes, and I'm trying to migrate to swift6
For this classes I've a facade that creates the classes for me without disclosing their internals, only conforming to a known protocol
I think I've hit a hard wall in my knowledge of how the actors can exchange data between themselves. I've created a small piece of code that can trigger the error I've hit
import SwiftUI
import Observation
@globalActor
actor MyActor {
static let shared: some Actor = MyActor()
init() {
}
}
@MyActor
protocol ProtocolMyActor {
var value: String { get }
func set(value: String)
}
@MyActor
func make(value: String) -> ProtocolMyActor {
return ImplementationMyActor(value: value)
}
class ImplementationMyActor: ProtocolMyActor {
private(set) var value: String
init(value: String) {
self.value = value
}
func set(value: String) {
self.value = value
}
}
@MainActor
@Observable
class ViewObserver {
let implementation: ProtocolMyActor
var value: String
init() async {
let implementation = await make(value: "Ciao")
self.implementation = implementation
self.value = await implementation.value
}
func set(value: String) {
Task {
await implementation.set(value: value)
self.value = value
}
}
}
struct MyObservedView: View {
@State var model: ViewObserver?
var body: some View {
if let model {
Button("Loaded \(model.value)") {
model.set(value: ["A", "B", "C"].randomElement()!)
}
} else {
Text("Loading")
.task {
self.model = await ViewObserver()
}
}
}
}
The error
Non-sendable type 'any ProtocolMyActor' passed in implicitly asynchronous call to global actor 'MyActor'-isolated property 'value' cannot cross actor boundary
Occurs in the init on the line "self.value = await implementation.value"
I don't know which concurrency error happens... Yes the init is in the MainActor , but the ProtocolMyActor data can only be accessed in a MyActor queue, so no data races can happen... and each access in my ImplementationMyActor uses await, so I'm not reading or writing the object from a different actor, I just pass sendable values as parameter to a function of the object..
can anybody help me understand better this piece of concurrency problem?
Thanks
similiar to
Error when debugging: Cannot creat… | Apple Developer Forums - https://developer.apple.com/forums/thread/651375
Xcode 12 beta 1 po command in de… | Apple Developer Forums - https://developer.apple.com/forums/thread/651157
which do not resolve this issue that I am encountering
Description of problem
I am seeing an error which prevents using lldb debugger on Swift code/projects. It is seen on any Swift or SwiftUI project that I've tried. This is the error displayed in lldb console when first breakpoint is encountered:
Cannot create Swift scratch context (couldn't create a ClangImporter)(lldb)
Xcode Version 12.3 (12C33)
macOS Big Sur Intel M1
Troubleshooting
I originally thought this was also working on an Intel Mac running Big Sur/Xcode 12.3, but was mistaken. Using my customized shell environment on the following setups, I encounter the same couldn't create a ClangImporter.
M1 Mac mini, main account (an "Admin" account)
same M1 Mac mini, new "dev" account (an "Admin" account)
Intel MBP, main account
They are all using an Intel Homebrew install, and my customized shell environment if that provides a clue?
I captured some lldb debugging info by putting expr types in ~/.lldbinit but the outputs were basically identical (when discounting scratch file paaths and memory addresses) compared to the "working clean" account log (described below)
log enable -f /tmp/lldb-log.txt lldb expr types
works in a "clean" user account
I created a new, uncustomized "Standard" testuser account on the M1 Mac mini, and launched the same system Xcode.app. There was no longer this error message, and was able to inspect variables at a swift program breakpoint in Swift context, including po symbol.
Impact
Effectively this makes the debugger in Swift on Xcode projects on my systems essentially unable to inspect Swift contexts' state.
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
}
}
Every time a (valid) vector instruction is added to the .s file, xcode report an error
(without vector instruction the .s file compile correctly)
By example
vand q8, q8, q10
found in https://developer.apple.com/forums/thread/104424
give an error
What I am missing to tell xcode to accept vector instruction ?
Topic:
Programming Languages
SubTopic:
General
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?
I am currently encountering two deprecated errors in my code. Could someone please identify the issues with the code?
Errors:
'init(coordinateRegion:interactionModes:showsUserLocation:userTrackingMode:annotationItems:annotationContent:)' was deprecated in iOS 17.0: Use Map initializers that take a MapContentBuilder instead.
'MapAnnotation' was deprecated in iOS 17.0: Use Annotation along with Map initializers that take a MapContentBuilder instead.
Code:
// MARK: - Stores Map (Dynamic)
struct StoresMapView: View {
@State private var storeLocations: [StoreLocation] = []
@State private var region = MKCoordinateRegion(
center: CLLocationCoordinate2D(latitude: -31.95, longitude: 115.86),
span: MKCoordinateSpan(latitudeDelta: 0.5, longitudeDelta: 0.5)
)
var body: some View {
Map(coordinateRegion: $region, interactionModes: .all, annotationItems: storeLocations) { store in
MapAnnotation(coordinate: CLLocationCoordinate2D(latitude: store.latitude, longitude: store.longitude)) {
VStack(spacing: 4) {
Image(systemName: "leaf.circle.fill")
.font(.title)
.foregroundColor(.green)
Text(store.name)
.font(.caption)
.fixedSize()
}
}
}
.onAppear(perform: loadStoreData)
.navigationTitle("Store Locator")
}
private func loadStoreData() {
guard let url = URL(string: "https://example.com/cop092/StoreLocations.json") else { return }
URLSession.shared.dataTask(with: url) { data, _, _ in
if let data = data, let decoded = try? JSONDecoder().decode([StoreLocation].self, from: data) {
DispatchQueue.main.async {
self.storeLocations = decoded
if let first = decoded.first {
self.region.center = CLLocationCoordinate2D(latitude: first.latitude, longitude: first.longitude)
}
}
}
}.resume()
}
}
I've been teaching myself Objective-C and I wanted to start creating projects that don't use ARC to become better at memory management and learn how it all works. I've been attempting to build and run applications, but I'm not really sure where to start as modern iOS development is used with Swift and memory management is handled.
Is there any way to create modern applications that use Objective-C, UIKit, and not use ARC?
Hey team I'm facing an issue where startDate is 1 January 2025 and endDate is 31 March 2025 between this 2 dates is 90 days, but on my code is being taken as 89 days
I've seen the math of the code excludes the first partial day (from midnight to 06:00) on 2025-01-01, which results in 89 full days instead of 90 days.
startDate: 2025-01-01 06:00:00 +0000
endDate: 2025-03-31 06:00:00 +0000
this is my function
func daysBetweenDates() -> Int? {
guard let selectedStartDate = selectedStartDate?.date else { return nil }
guard let selectedEndDate = selectedEndDate?.date else { return 0 }
let calendar = Calendar.current
let dateComponents = calendar.dateComponents([.day], from: selectedStartDate, to: selectedEndDate)
return dateComponents.day
}
what I've tried is reset the hours to 0 so it can take the full day and return 90 days
like this
func daysBetweenDates() -> Int? {
guard let selectedStartDate = selectedStartDate?.date else { return nil }
guard let selectedEndDate = selectedEndDate?.date else { return 0 }
var calendar = Calendar(identifier: .gregorian)
calendar.timeZone = TimeZone(secondsFromGMT: 0) ?? .current
let cleanMidNightStartDate = calendar.startOfDay(for: selectedStartDate)
let cleanMidNightEndDate = calendar.startOfDay(for: selectedEndDate.addingTimeInterval(24 * 60 * 60))
let dateComponents = calendar.dateComponents([.day], from: cleanMidNightStartDate, to: cleanMidNightEndDate)
let daysCount = dateComponents.day ?? 0
return daysCount
}
this worked for that date specifically but when I tried to change the date for example
startDate: 18 December 2024.
endDate: 18 March 2025.
between those dates we have 90 days but this function now reads 91.
what I'm looking is a cleaver solution for this problem so I can have the best posible quality code, thanks in advance!
Topic:
Programming Languages
SubTopic:
Swift
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?
Hi all,
In Swift, I often see static helper functions grouped in an enum without any cases, like this:
enum StringUtils {
static func camelCaseToSnakeCase(_ input: String) -> String {
// implementation
}
}
Since this enum has no cases, it cannot be instantiated – which is exactly the point.
It’s meant to group related functionality without any stored state, and without the need for instantiation.
This pattern avoids writing a struct with a private init() and makes the intent clearer:
"This is just a static utility, not an object."
You’ll often see this used for things like:
AnalyticsEvents.track(_:)
My question:
Is this use of a case-less enum considered good practice in Swift when building static-only helpers?
Or is there a better alternative for expressing intent and preventing instantiation?
I’d appreciate any insight – especially if there’s official guidance or references from the Swift core team.
Thanks!
Topic:
Programming Languages
SubTopic:
Swift
I have a Settings class that conform to the TestProtocol. From the function of the protocol I need to call the setString function and this function needs to be on the MainActor. Is there a way of make this work in Swift6, without making the protocol functions running on @MainActor
The calls are as follows:
class Settings: TestProtocol{
var value:String = ""
@MainActor func setString( _ string:String ){
value = string
}
func passString(string: String) {
Task{
await setString(string)
}
}
}
protocol TestProtocol{
func passString( string:String )
}
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
We have FrameworkA which needs to use another FrameworkB internally to fetch a token.
Now when I try to use this FrameworkA, we are seeing an issue with internal framework i.e. No such module 'FrameworkB'.
But when I use @_implementationOnly import for the internal FrameworkB, I didn't see any issues.
So just wanted to check If I can go ahead and use this @_implementationOnly import flag in Production?
We are migrating to swift 6 from swift 5 using Xcode 16.2. we are getting below errors in almost each of our source code files :
Call to main actor-isolated initializer 'init(storyboard:bundle:)' in a synchronous non isolated context
Main actor-isolated property 'delegate' can not be mutated from a nonisolated context
Call to main actor-isolated instance method 'register(cell:)' in a synchronous nonisolated context
Call to main actor-isolated instance method 'setup()' in a synchronous nonisolated context
Few questions related to these compile errors.
Some of our functions arguments have default value set but swift 6 does not allow to set any default values. This requires a lot of code changes throughout the project. This would be lot of source code re-write.
Using annotations like @uncheck sendable , @Sendable on the class (Main actor) name, lot of functions within those classes , having inside some code which coming from other classes which also showing main thread issue even we using @uncheck sendable.
There are so many compile errors, we are still seeing other than what we have listed here. Fixing these compile errors throughout our project, would be like a re-write of our whole application, which would take lot of time. In order for us to migrate efficiently, we have few questions where we need your help with. Below are the questions.
Are there any ways we can bypass these errors using any keywords or any other way possible?
Can Swift 5 and Swift 6 co-exist? so, we can slowly migrate over a period of time.
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)