I am experiencing memory leaks in my iOS app that seem to be related to an issue between UIInputView and _UIInputViewContent. After using the memory graph, I'm seeing that instances of these objects aren't being deallocated properly.
The UIInputViewController whichs holds the inputView is being deallocated properly along with its subviews.I have tried to remove all of UIInputViewController's subviews and their functions but the uiInputView is not being deallocated.
The current setup of my app is a collectionView with multiple cell,each possessing a textfield with holds a UIInputViewController.When i scroll up or down,the views are being reused as expected and the number of UIInputViewController stays consistent with the number of textfields.However the number of inputView keeps increasing referencing solely _UIInputViewContent.
class KeyboardViewController: UIInputViewController {
// Callbacks
var key1: ((String) -> Void)?
var key2: (() -> Void)?
var key3: (() -> Void)?
var key4: (() -> Void)?
private lazy var buttonTitles = [
["1", "2", "3"],
["4", "5", "6"],
["7", "8", "9"]
]
override func viewDidLoad() {
super.viewDidLoad()
setupKeyboard()
}
lazy var mainStackView: UIStackView = {
let mainStackView = UIStackView()
mainStackView.axis = .vertical
mainStackView.distribution = .fillEqually
mainStackView.spacing = 16
mainStackView.translatesAutoresizingMaskIntoConstraints = false
return mainStackView
}()
private func setupKeyboard() {
let keyboardView = UIView(frame:CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: 279.0))
keyboardView.addSubview(mainStackView)
NSLayoutConstraint.activate([
mainStackView.topAnchor.constraint(equalTo: keyboardView.topAnchor, constant: 16),
mainStackView.leadingAnchor.constraint(equalTo: keyboardView.leadingAnchor, constant: 0),
mainStackView.trailingAnchor.constraint(equalTo: keyboardView.trailingAnchor, constant: -24),
mainStackView.bottomAnchor.constraint(equalTo: keyboardView.bottomAnchor, constant: -35)
])
// Create rows
for (_, _) in buttonTitles.enumerated() {
let rowStackView = UIStackView()
rowStackView.axis = .horizontal
rowStackView.distribution = .fillEqually
rowStackView.spacing = 1
// Create buttons for each row
for title in rowTitles {
let button = createButton(title: title)
rowStackView.addArrangedSubview(button)
}
mainStackView.addArrangedSubview(rowStackView)
}
self.view = keyboardView
}
private func createButton(title: String) -> UIButton {
switch title {
///returns a uibutton based on title
}
}
// MARK: - Button Actions
@objc private func numberTapped(_ sender: UIButton) {
if let number = sender.title(for: .normal) {
key1?(number)
}
}
@objc private func key2Called() {
key2?()
}
@objc private func key3Called() {
key3?()
}
@objc private func key4Called() {
key4?()
}
deinit {
// Clear any strong references
key1 = nil
key2 = nil
key3 = nil
key4 = nil
for subview in mainStackView.arrangedSubviews {
if let stackView = subview as? UIStackView {
for button in stackView.arrangedSubviews {
(button as? UIButton)?.removeTarget(self, action: nil, for: .allEvents)
}
}
}
mainStackView.removeFromSuperview()
}
}
Environment
iOS 16.3
Xcode 18.3.1
Any insights would be greatly appreciated as this is causing noticeable memory growth in my app over time.
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Is it ok for an Actor type to have a Publisher as a property to let others observe changes over time? Or use the @Published property wrapper to achieve this?
actor MyActor {
var publisher = PassthroughSubject<Int, Never>()
var data: Int {
didSet {
publisher.send(data)
}
}
...
}
// Usage
var tasks = Set<AnyCancellable>()
let actor = MyActor()
Task {
let publisher = await actor.publisher
publisher.sink { print($0) }.store(in: &tasks)
}
This seems like this should be acceptable. I would expect a Publisher to be thread safe, and as long as the Output is a value type things should be fine.
I have been getting random EXC_BAD_ACCESS errors when using this approach. But turning on the address sanitizer causes these crashes to go away. I know that isn't very specific but I wanted to start by seeing if this type of pattern is ok to do.
We’ve noticed an unexpected behavior in our production iOS app where the UIDevice.current.identifierForVendor value occasionally changes, even though:
The app is distributed via the App Store (not TestFlight or Xcode builds)
We do not switch provisioning profiles or developer accounts
No App Clips, App Thinning, or other advanced features are in use
There’s no manual reinstall or device reset in the scenarios observed (as per user feedback)
Any insights or confirmations would be much appreciated.
Thanks!
Hi,
In mac os swift ui application when i set window.isReleasedWhenClosed and when i close the window the app is getting crashed with exc_bad_access. but when i leave it to default value the app is not crashing. for some windows setting window.isReleasedWhenClosed to true is woking properly when closing the windows. But for some windows it is crashing. If i dont set it to true the window is not removed from NSApplication.shared.windows sometimes. I am confused about setting isReleasedWhenClosed to true
Could someone calrify on this please.
thank in advance.
I'm working on implementing file moving with NSFileCoordinator. I'm using the slightly newer asynchronous API with the NSFileAccessIntents. My question is, how do I go about notifying the coordinator about the item move? Should I simply create a new instance in the asynchronous block? Or does it need to be the same coordinator instance?
let writeQueue = OperationQueue()
public func saveAndMove(data: String, to newURL: URL) {
let oldURL = presentedItemURL!
let sourceIntent = NSFileAccessIntent.writingIntent(with: oldURL, options: .forMoving)
let destinationIntent = NSFileAccessIntent.writingIntent(with: newURL, options: .forReplacing)
let coordinator = NSFileCoordinator()
coordinator.coordinate(with: [sourceIntent, destinationIntent], queue: writeQueue) { error in
if let error {
return
}
do {
// ERROR: Can't access NSFileCoordinator because it is not Sendable (Swift 6)
coordinator.item(at: oldURL, willMoveTo: newURL)
try FileManager.default.moveItem(at: oldURL, to: newURL)
coordinator.item(at: oldURL, didMoveTo: newURL)
} catch {
print("Failed to move to \(newURL)")
}
}
}
Topic:
App & System Services
SubTopic:
Processes & Concurrency
Tags:
Files and Storage
Swift
iCloud Drive
Concurrency
I would like to modify the content of a published LocationNode upon been clicked by the user. But unfortunately:
func hitTest(_ point: CGPoint, options: [SCNHitTestOption : Any]? = nil) -> [SCNHitTestResult]
returns an SCNNode array from which it is impossible to retrieve the original LocationNode being inserted in order to be able to modify it.
Of course the solution would be to either insert the SCNNode corresponding to the inserted LocationNode in a custom class or conversely insert the identifier of the custom object as a tag of the LocationNode, in order to solve the issue. But both options seem impossible to implement.
May anyone help me?
I'm integrating Apple Pay with PayFort in a Swift iOS application, and I’m currently working on preparing a valid purchase request using Apple Pay, as described in PayFort’s documentation:
🔗 https://docsbeta.payfort.com/docs/api/build/index.html?shell#apple-pay-authorization-purchase-request
The documentation outlines the following required parameters:
apple_data
apple_signature
apple_header
apple_transactionId
apple_ephemeralPublicKey
apple_publicKeyHash
apple_paymentMethod
apple_displayName
apple_network
apple_type
Optional: apple_applicationData
I understand these should be derived from the PKPayment object after Apple Pay authorization, but I’m having trouble mapping everything correctly. Here’s what I’m seeing in code:
payment.token
// Returns something like: <PKPaymentToken: 0x28080ae80; transactionIdentifier: "..."; paymentData: 3780 bytes>
payment.token.paymentData
// Contains 3780 bytes of encrypted data
payment.token.paymentData.base64EncodedString()
// Returns a long base64 string, which at first glance seems like it could be used for apple_data,
// but PayFort doesn't accept it as-is — so this value appears to be incomplete or incorrectly formatted
I can successfully retrieve the following values from payment.token.paymentMethod:
apple_displayName
apple_network
apple_type
However, I’m still unsure how to extract or build the following in the format accepted by PayFort:
apple_data
apple_signature
apple_header
apple_transactionId
apple_ephemeralPublicKey
apple_publicKeyHash
apple_paymentMethod
These may be contained within the paymentData JSON, but I’m not sure how to decode it or if Apple allows decrypting it in a way that matches PayFort’s expected format.
How can I correctly extract or build apple_data, apple_signature, and apple_header from the Apple Pay token?
Also, how should I handle the decryption or decoding (if necessary) of paymentData to retrieve values like apple_transactionId, apple_ephemeralPublicKey, and apple_publicKeyHash?
If anyone has successfully set this up or has example code that bridges Apple Pay and PayFort’s expected request format, it would be super helpful!
Thanks in advance 🙏
Hi there!
Sorry in advance, this is going to be a long post of Apple developer pains which I want to share with you, and, hopefully, find the answer and help Apple become better.
I'm at the very beginning of my new and exciting personal project which (I hope) may one day feed me and be my daily source of inspiration. I'm not a newbie in Apple development nor am I a senior-level developer — just a fellow developa'.
Here's the problem I bring to you — why Apple promotes Unified Logging System and recommends using it as the primary way to implement logging in 3rd-party apps? No doubt, OSLog is a great, secure, efficient, and centralized way to gather diagnostics information, and I, starting my new project, am itching to choose exactly this 1st-party logging infrastructure. This decision in theory has a number of benefits:
I don't have to depend on 3rd-party logging frameworks which may eventually be discontinued;
I have extensive documentation, great WWDC sessions explaining how to use the framework, and stackoverflow answers from the whole Apple dev community in case I experience any troubles;
I have this cool Console.app and upcoming Xcode 15 tools with great visualization and filtering of my logs;
It's quite a robust and stable infrastructure which I may restfully rely on.
But... the thing is there's this big elephant in the room — this API is non-customizable, inconvenient, and hard to use in terms of the app architecture. I can't write my own protocol wrapper around it to abstract my domain logic from implementation details or just simplify the usage at the call site. I can't configure my own format for log messages (this is debatable, since Console.app doesn't provide "naked strings" as Xcode 14 and earlier, but still). And what's most important — I can't conveniently retrieve the logs!
I can't implement the functionality where my user just taps the button, and the logs are sent on the background queue to my support email (eskimo's answer). They would have to go through this monstrous procedure of holding volume buttons on the iPhone, connecting their device to the Mac, gathering sysdiagnose, entering some weird Terminal commands (jeez, these nerdy developers...), etc. If it ever succeeds, of course, and something doesn't go wrong, leaving my user angry and dissatisfied with my app.
Regarding the protocol wrapper, I can't do something like this:
protocol Logging {
var logger: Logger { get }
func info(_ message: OSLogMessage)
}
extension Logging {
var logger: Logger {
return Logger(
subsystem: "com.my.bundle.id",
category: String(describing: Self.self)
)
}
func info(_ message: OSLogMessage) {
logger.info(message)
}
}
class MyClass: Logging {
func someImportantMethod() {
// ...
self.info("Some useful debug info: \(someVar, privacy: .public)")
}
}
I've been investigating this topic for 2 days, and it's the farthest I want to go in beating my head over how to do two simple things:
How to isolate logging framework implementation decision from my main code and write convenience wrappers?
How to easily transfer the log files from the user to the developer?
And I'm not the only one struggling. Here's just one example among hundreds of other questions that are being asked on dev forums: https://www.hackingwithswift.com/forums/ios/unified-logging-system-retrieve-logs-on-device/838. I've read almost all Apple docs which describe the modern Unified Logging System, I've read through eskimo's thread on Apple Developer Forum about the API, but I still haven't found the answer.
Maybe, I've misperceived this framework and it's not the tool I'm searching for? Maybe, it focuses on different aspects of logging, e.g. signposting, rather than logging the current state of the app? What am I missing?
When i try to set the value ‘false’ for ‘usesClassicLoadingMode’ it is getting crashed.
The crash logs has been shared below
Ex:
let config = URLSessionConfiguration.default
if #available(iOS 18.4, *) {
config.usesClassicLoadingMode = false
}
Error log :
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFBoolean objectForKeyedSubscript:]: unrecognized selector sent to instance 0x1f655c390'
*** First throw call stack:
(0x188ae52ec 0x185f69a7c 0x188b4f67c 0x1889fcb84 0x1889fc4f0 0x191393bc8 0x1889ec8a0 0x1889ec6e4 0x191393ad0 0x191344dac 0x191344b58 0x107cfa064 0x107ce36d0 0x191343fcc 0x1891b3b18 0x1892dae58 0x189235c60 0x18921e270 0x18921d77c 0x18921a8ac 0x107ce0584 0x107cfa064 0x107ce891c 0x107ce95d8 0x107ceabcc 0x107cf5894 0x107cf4eb0 0x212f51660 0x212f4e9f8)
terminating due to uncaught exception of type NSException
Can you please provider the resolution steps
Hi,
I am getting an error stating "Argument passed to call that takes no arguments". I want this Apple Watch App to measure and store RR Intervals from the PPG sensor on the Apple Watch for Heart Rate Variability calculations. Please help me fix this, I can't figure it out. Here is my code:
heartbeatQuery = HKHeartbeatSeriesQuery(predicate: predicate,
dataReceivedHandler: { (query, timeSinceLastBeat, ended, error) in
// Switch to main thread for UI updates
DispatchQueue.main.async {
if let error = error {
print("Heartbeat query error: (error.localizedDescription)")
self.fetchErrorMessage = "Heartbeat query error: (error.localizedDescription)"
// Consider stopping the workout session if the query fails critically
// self.stopWorkoutSession()
return
}
if ended {
print("Heartbeat query indicates series ended.")
}
// Append valid RR intervals
if timeSinceLastBeat > 0 {
self.rrIntervals.append(timeSinceLastBeat)
self.beatCount += 1
}
} // End DispatchQueue.main.async
}) // End query data handler
// --- END OF PROBLEMATIC INITIALIZER ---
// Execute the query if it was created successfully
It recommends the fix as removing this part:
'(predicate: predicate,
dataReceivedHandler: { (query, timeSinceLastBeat, ended, error) in
// Switch to main thread for UI updates
DispatchQueue.main.async {
if let error = error {
print("Heartbeat query error: (error.localizedDescription)")
self.fetchErrorMessage = "Heartbeat query error: (error.localizedDescription)"
// Consider stopping the workout session if the query fails critically
// self.stopWorkoutSession()
return
}
if ended {
print("Heartbeat query indicates series ended.")
}
// Append valid RR intervals
if timeSinceLastBeat > 0 {
self.rrIntervals.append(timeSinceLastBeat)
self.beatCount += 1
}
} // End DispatchQueue.main.async
})'
But after I remove that it says "Cannot assign value of type 'HKHeartbeatSeriesQuery.Type' to type 'HKHeartbeatSeriesQuery'" PLEASE HELP ME
Thanks
I have an error issue that I haven’t been able to solve despite doing extensive research. In fact the similar examples I have found so far have been educational but I have not been able to make work. The example below I am hoping will be easy to fix as it is only producing errors with one line of code…
import SwiftUI
import CoreLocation
var currentLon = Double()
var currentLat = Double()
extension CLLocation {
class func distance(from: CLLocationCoordinate2D, to: CLLocationCoordinate2D) -> CLLocationDistance {
let from = CLLocation(latitude: from.latitude, longitude: from.longitude)
let to = CLLocation(latitude: to.latitude, longitude: to.longitude)
return from.distance(from: to)
}
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
currentLon = (locations.last?.coordinate.longitude)!
currentLat = (locations.last?.coordinate.latitude)!
}/*⚠️ Not sure if this function will work? (Update User Location coordinates on the move?)*/
}
struct Positions: Identifiable {
let id = UUID()
let name: String
let latitude: Double
let longitude: Double
var coordinate: CLLocationCoordinate2D {
CLLocationCoordinate2D(latitude: latitude, longitude: longitude)
}
}
struct GameMapView: View {
let from = CLLocationCoordinate2D(latitude: currentLon, longitude: currentLat)
let to = CLLocationCoordinate2D(latitude: thisCardPositionLongitude, longitude: thisCardPositionLongitude)
let distanceFrom = from.distance(from: to)
/*⚠️ ERRORS:
1. Cannot use instance member 'from' within property initializer; property initializers run before 'self' is available.
2. Cannot use instance member 'to' within property initializer; property initializers run before 'self' is available.
3. Value of type 'CLLocationCoordinate2D' has no member 'distance'. */
@State private var region = MKCoordinateRegion(
center: CLLocationCoordinate2D(
latitude: thisCardPositionLatitude,
longitude: thisCardPositionLongitude),
span: MKCoordinateSpan(
latitudeDelta: 0.0001,
longitudeDelta: 0.0001)
)
var body: some View {
Map(coordinateRegion: $region,
showsUserLocation: true,
annotationItems: locations){ place in
MapMarker(coordinate: place.coordinate,tint: Color.accentColor)
}
.edgesIgnoringSafeArea(.all)
VStack {
Print("Distance from Location: \(distanceFrom)")
font(.largeTitle)
padding()
}
Topic:
App & System Services
SubTopic:
Maps & Location
Tags:
Swift Playground
Swift
MapKit
Maps and Location
I'm building a Live Activity using ActivityKit in iOS, and I'm trying to understand how apps like Uber or Lyft manage to keep the Dynamic Island always in its expanded state, without transitioning through the compact phase.
In my implementation, the Live Activity always starts in the compact state, and only expands temporarily when I interact with it. I've tried the following:
Updating the ContentState frequently using activity.update(using:)
I tried updating the activity every 1 second, but it didn’t make a difference.
Leaving the compactLeading, compactTrailing, and minimal regions empty using EmptyView() — also didn’t change the behavior.
Delaying the initial update by 1 second — no effect.
What I'm trying to figure out:
Is there any way to programmatically force or request the Dynamic Island to stay in the expanded state?
Could this behavior be achieved through push updates, using apns-push-type: liveactivity and a high priority (apns-priority)?
What I’m trying to achieve is similar to the behavior shown in the images below — the apps do not transition to the compact island, but instead displays the expanded view immediately.
Example:
I Am interested in coding, and built my fist app that is an app that has a picture of Niagara Falls with corner radius of 10, But, every time I start the build, it says: Thread 1: EXC_BAD_ACCESS (code=2, address=0x16b123f20) not sure what to do now.
I have developed a sample app following the example found Updating your app package installer to use the new Service Management API and referring this discussion on XPC Security.
The app is working fine, I have used Swift NSXPCConnection in favour of xpc_connection_create_mach_service used in the example. (I am running app directly from Xcode)
I am trying to set up security requirements for the client connection using setCodeSigningRequirement on the connection instance.
But it fails for even basic requirement connection.setCodeSigningRequirement("anchor apple").
Error is as follows.
cannot open file at line 46986 of [554764a6e7]
os_unix.c:46986: (0) open(/private/var/db/DetachedSignatures) - Undefined error: 0
xpc_support_check_token: anchor apple error: Error Domain=NSOSStatusErrorDomain Code=-67050 "(null)" status: -67050
I have used codesign -d --verbose=4 /path/to/executable to check the attributes I do get them in the terminal.
Other way round, I have tried XPC service provider sending back process id (pid) with each request, and I am probing this id to get attributes using this code which gives all the details.
func inspectCodeSignature(ofPIDString pidString: String) {
guard let pid = pid_t(pidString) else {
print("Invalid PID string: \(pidString)")
return
}
let attributes = [kSecGuestAttributePid: pid] as CFDictionary
var codeRef: SecCode?
let status = SecCodeCopyGuestWithAttributes(nil, attributes, [], &codeRef)
guard status == errSecSuccess, let code = codeRef else {
print("Failed to get SecCode for PID \(pid) (status: \(status))")
return
}
var staticCode: SecStaticCode?
let staticStatus = SecCodeCopyStaticCode(code, [], &staticCode)
guard staticStatus == errSecSuccess, let staticCodeRef = staticCode else {
print("Failed to get SecStaticCode (status: \(staticStatus))")
return
}
var infoDict: CFDictionary?
if SecCodeCopySigningInformation(staticCodeRef, SecCSFlags(rawValue: kSecCSSigningInformation), &infoDict) == errSecSuccess,
let info = infoDict as? [String: Any] {
print("🔍 Code Signing Info for PID \(pid):")
print("• Identifier: \(info["identifier"] ?? "N/A")")
print("• Team ID: \(info["teamid"] ?? "N/A")")
if let entitlements = info["entitlements-dict"] as? [String: Any] {
print("• Entitlements:")
for (key, value) in entitlements {
print(" - \(key): \(value)")
}
}
} else {
print("Failed to retrieve signing information.")
}
var requirement: SecRequirement?
if SecRequirementCreateWithString("anchor apple" as CFString, [], &requirement) == errSecSuccess,
let req = requirement {
let result = SecStaticCodeCheckValidity(staticCodeRef, [], req)
if result == errSecSuccess {
print("Signature is trusted (anchor apple)")
} else {
print("Signature is NOT trusted by Apple (failed anchor check)")
}
}
var infoDict1: CFDictionary?
let signingStatus = SecCodeCopySigningInformation(staticCodeRef, SecCSFlags(rawValue: kSecCSSigningInformation), &infoDict1)
guard signingStatus == errSecSuccess, let info = infoDict1 as? [String: Any] else {
print("Failed to retrieve signing information.")
return
}
print("🔍 Signing Info for PID \(pid):")
for (key, value) in info.sorted(by: { $0.key < $1.key }) {
print("• \(key): \(value)")
}
}
If connection.setCodeSigningRequirement does not works I plan to use above logic as backup.
Q: Please advise is there some setting required to be enabled or I have to sign code with some flags enabled.
Note: My app is not running in a Sandbox or Hardened Runtime, which I want.
Dare anyone try the following code in any Playground:
// Define a model that conforms to Codable
struct User: Codable {
var name: String
var age: Int
var email: String?
}
// JSON data (as a string for demonstration)
let jsonString = """
{
"name": "John Doe",
"age": 30,
"email": "john@example.com"
}
"""
// Convert the JSON string to Data
if let jsonData = jsonString.data(using: .utf8) {
do {
// Parse the JSON data into the User model
let user = try JSONDecoder().decode(User.self, from: jsonData)
print("Name: \(user.name), Age: \(user.age), Email: \(user.email ?? "N/A")")
} catch {
print("Error decoding JSON: \(error)")
}
}
I tested with Xcode 16.2 and latest 16.3, it reliably crashes the lldb server!
Version: iOS 18.1 and later (works as expected on iOS 18.0 and earlier)
Area: SpringBoard / Notification Center / App Icon Rendering
Description: When changing the app's alternate icon using UIApplication.setAlternateIconName(_:completionHandler:), the icon is updated correctly on the Home Screen and App Switcher. However, in Notification Center, the old app icon is still shown for notifications, even after the change has completed. This issue only occurs on iOS 18.1 and later. In iOS 18.0 and earlier, Notification Center correctly reflects the updated icon.
- Steps to reproduce:
Create an iOS app with alternate app icons configured in the Info.plist.
Use UIApplication.shared.setAlternateIconName("IconName") to change the icon at runtime.
Send a notification.
Pull down Notification Center and observe the icon shown beside the notification.
- Expected Behavior:
Notification Center should reflect the updated (alternate) app icon immediately after the change.
- Actual Behavior:
Notification Center continues to display the old (primary) app icon. The new icon appears correctly on the Home Screen and App Switcher. Restarting the device does cause Notification Center to update and reflect the correct icon, which suggests a cache or refresh issue in SpringBoard or Notification Center.
- Notes:
Issue introduced in iOS 18.1; not present in 18.0.
Reproduces on both physical devices and simulators.
Occurs with both scheduled local notifications and remote notifications.
Restarting the device updates the Notification Center icon, but this is not a viable user-facing workaround.
Topic:
App & System Services
SubTopic:
Notifications
Tags:
Swift
APNS
User Notifications
Notification Center
I am trying to achieve an animated gradient effect that changes values over time based on the current seconds. I am also using AVPlayer and AVMutableVideoComposition along with custom instruction and class to generate the effect. I didn't want to load any video file, but rather generate a custom video with my own set of instructions. I used Metal Compute shaders to generate the effects and make the video to be 20 seconds.
However, when I run the code, I get a frozen player with the gradient applied, but when I try to play the video, I get this warning in the console :- Visual isTranslatable: NO; reason: observation failure: noObservations
Here is the screenshot :-
My entire code :-
import AVFoundation
import Metal
class GradientVideoCompositorTest: NSObject, AVVideoCompositing {
var sourcePixelBufferAttributes: [String: Any]? = [
kCVPixelBufferPixelFormatTypeKey as String: kCVPixelFormatType_32BGRA
]
var requiredPixelBufferAttributesForRenderContext: [String: Any] = [
kCVPixelBufferPixelFormatTypeKey as String: kCVPixelFormatType_32BGRA
]
private var renderContext: AVVideoCompositionRenderContext?
private var metalDevice: MTLDevice!
private var metalCommandQueue: MTLCommandQueue!
private var metalLibrary: MTLLibrary!
private var metalPipeline: MTLComputePipelineState!
override init() {
super.init()
setupMetal()
}
func setupMetal() {
guard let device = MTLCreateSystemDefaultDevice(),
let queue = device.makeCommandQueue(),
let library = try? device.makeDefaultLibrary(),
let function = library.makeFunction(name: "gradientShader") else {
fatalError("Metal setup failed")
}
self.metalDevice = device
self.metalCommandQueue = queue
self.metalLibrary = library
self.metalPipeline = try? device.makeComputePipelineState(function: function)
}
func renderContextChanged(_ newRenderContext: AVVideoCompositionRenderContext) {
renderContext = newRenderContext
}
func startRequest(_ request: AVAsynchronousVideoCompositionRequest) {
guard let outputPixelBuffer = renderContext?.newPixelBuffer(),
let metalTexture = createMetalTexture(from: outputPixelBuffer) else {
request.finish(with: NSError(domain: "com.example.gradient", code: -1, userInfo: nil))
return
}
var time = Float(request.compositionTime.seconds)
renderGradient(to: metalTexture, time: time)
request.finish(withComposedVideoFrame: outputPixelBuffer)
}
private func createMetalTexture(from pixelBuffer: CVPixelBuffer) -> MTLTexture? {
var texture: MTLTexture?
let width = CVPixelBufferGetWidth(pixelBuffer)
let height = CVPixelBufferGetHeight(pixelBuffer)
let textureDescriptor = MTLTextureDescriptor.texture2DDescriptor(
pixelFormat: .bgra8Unorm,
width: width,
height: height,
mipmapped: false
)
textureDescriptor.usage = [.shaderWrite, .shaderRead]
CVPixelBufferLockBaseAddress(pixelBuffer, .readOnly)
if let textureCache = createTextureCache(), let cvTexture = createCVMetalTexture(from: pixelBuffer, cache: textureCache) {
texture = CVMetalTextureGetTexture(cvTexture)
}
CVPixelBufferUnlockBaseAddress(pixelBuffer, .readOnly)
return texture
}
private func renderGradient(to texture: MTLTexture, time: Float) {
guard let commandBuffer = metalCommandQueue.makeCommandBuffer(),
let commandEncoder = commandBuffer.makeComputeCommandEncoder() else { return }
commandEncoder.setComputePipelineState(metalPipeline)
commandEncoder.setTexture(texture, index: 0)
var mutableTime = time
commandEncoder.setBytes(&mutableTime, length: MemoryLayout<Float>.size, index: 0)
let threadsPerGroup = MTLSize(width: 16, height: 16, depth: 1)
let threadGroups = MTLSize(
width: (texture.width + 15) / 16,
height: (texture.height + 15) / 16,
depth: 1
)
commandEncoder.dispatchThreadgroups(threadGroups, threadsPerThreadgroup: threadsPerGroup)
commandEncoder.endEncoding()
commandBuffer.commit()
}
private func createTextureCache() -> CVMetalTextureCache? {
var cache: CVMetalTextureCache?
CVMetalTextureCacheCreate(kCFAllocatorDefault, nil, metalDevice, nil, &cache)
return cache
}
private func createCVMetalTexture(from pixelBuffer: CVPixelBuffer, cache: CVMetalTextureCache) -> CVMetalTexture? {
var cvTexture: CVMetalTexture?
let width = CVPixelBufferGetWidth(pixelBuffer)
let height = CVPixelBufferGetHeight(pixelBuffer)
CVMetalTextureCacheCreateTextureFromImage(
kCFAllocatorDefault,
cache,
pixelBuffer,
nil,
.bgra8Unorm,
width,
height,
0,
&cvTexture
)
return cvTexture
}
}
class GradientCompositionInstructionTest: NSObject, AVVideoCompositionInstructionProtocol {
var timeRange: CMTimeRange
var enablePostProcessing: Bool = true
var containsTweening: Bool = true
var requiredSourceTrackIDs: [NSValue]? = nil
var passthroughTrackID: CMPersistentTrackID = kCMPersistentTrackID_Invalid
init(timeRange: CMTimeRange) {
self.timeRange = timeRange
}
}
func createGradientVideoComposition(duration: CMTime, size: CGSize) -> AVMutableVideoComposition {
let composition = AVMutableComposition()
let instruction = GradientCompositionInstructionTest(timeRange: CMTimeRange(start: .zero, duration: duration))
let videoComposition = AVMutableVideoComposition()
videoComposition.customVideoCompositorClass = GradientVideoCompositorTest.self
videoComposition.renderSize = size
videoComposition.frameDuration = CMTime(value: 1, timescale: 30) // 30 FPS
videoComposition.instructions = [instruction]
return videoComposition
}
#include <metal_stdlib>
using namespace metal;
kernel void gradientShader(texture2d<float, access::write> output [[texture(0)]],
constant float &time [[buffer(0)]],
uint2 id [[thread_position_in_grid]]) {
float2 uv = float2(id) / float2(output.get_width(), output.get_height());
// Animated colors based on time
float3 color1 = float3(sin(time) * 0.8 + 0.1, 0.6, 1.0);
float3 color2 = float3(0.12, 0.99, cos(time) * 0.9 + 0.3);
// Linear interpolation for gradient
float3 gradientColor = mix(color1, color2, uv.y);
output.write(float4(gradientColor, 1.0), id);
}
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.
and yeah, swift vaguely is reminiscent of a programming language I developed, but
I want swift To do
return if (var blah:Int32 == 43){
blah = blah2;
}
your welcome !! thank me on my new accounting job lol =/
basically I want to return conditional statements for a private reason
I have a macro that converts expression into a string literal, e.g.:
#toString(variable) -> "variable"
#toString(TypeName) -> "TypeName"
#toString(\TypeName.property) -> "property"
In Xcode 16.3 #toString(TypeName) stopped to work, compilation throws 'Expected member name or initializer call after type name' error.
Everything works fine in Xcode 16.2. I tried to compare build settings between 16.2 and 16.3 but haven't noticed differences that may cause this new error.
The following works in both Xcode versions:
#toString(variable) -> "variable"
#toString(\TypeName.property) -> "property"
Seems like Xcode tries to compile code that shouldn't be compiled because of macro expansion.
Does anybody know what new has appeared in 16.3 and, perhaps, how to fix the problem?