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So if I create an Alias of a folder in Finder and hand the alias to my app (I also moved the alias file to a new folder, but I did not move the original folder)...so then my app resolves the alias using: NSURL +URLByResolvingAliasFileAtURL: What happens? The resolved URL points to a completely different folder. Well not completely different. It resolves to a folder that happens to share same last path component as the original folder...but this folder is inside the same parent folder the alias file is in. It does not resolve to the original folder I created the alias of. So then once my app touches the alias with +URLByResolvingAliasFileAtURL: the alias now resolves to this new (wrong) location (even in Finder). Couple details: My app is not sandboxed. I have permission to access the original folder in my app (but even if I didn't the alias shouldn't be mutated just by merely resolving it). Only seems to happen if the folder I move the alias to happens to contain a sibling folder that has the same title as the original folder. Like it's just deleting the last path component of the alias and then appending the last path component of the original filename and just going with that. I hope that makes sense. I tried creating the alias myself using -bookmarkDataWithOptions: and going the other way (to Finder) but Finder must be resolving the alias using a different API because it resolves to the original location as expected.

I'll try to ask a question that makes sense this time :) . I'm using the following method on NSFileManager: (BOOL) getRelationship:(NSURLRelationship *) outRelationship ofDirectoryAtURL:(NSURL *) directoryURL toItemAtURL:(NSURL *) otherURL error:(NSError * *) error; Sets 'outRelationship' to NSURLRelationshipContains if the directory at 'directoryURL' directly or indirectly contains the item at 'otherURL', meaning 'directoryURL' is found while enumerating parent URLs starting from 'otherURL'. Sets 'outRelationship' to NSURLRelationshipSame if 'directoryURL' and 'otherURL' locate the same item, meaning they have the same NSURLFileResourceIdentifierKey value. If 'directoryURL' is not a directory, or does not contain 'otherURL' and they do not locate the same file, then sets 'outRelationship' to NSURLRelationshipOther. If an error occurs, returns NO and sets 'error'. So this method falsely returns NSURLRelationshipSame for different directories. One is empty, one is not. Really weird behavior. Two file path urls pointing to two different file paths have the same NSURLFileResourceIdentifierKey? Could it be related to https://developer.apple.com/forums/thread/813641 ? One url in the check lived at the same file path as the other url at one time (but no longer does). No symlinks or anything going on. Just plain directory urls. And YES calling -removeCachedResourceValueForKey: with NSURLFileResourceIdentifierKey causes proper result of NSURLRelationshipOther to be returned. And I'm doing the check on a background queue.

When I end editing pressing the escape key, the system sometimes plays NSBeep(). I noticed this with NSBrowser. Every time I press escape to end editing the system beeps. At first I thought it was somewhere in my app but I set a symbolic breakpoint and discovered it was not coming from my code. I filed FB22127038. Since then I discovered that NSBeep playing at inappropriate times is not exclusive to NSBrowser. It appears if there is a NSTableView in the window and you just press the escape key (even if you aren't editing anything) AppKit beeps. It can be traced to: #0 0x0000000199e3184c in NSBeep () #1 0x000000019aa03fac in -[NSWindow doCommandBySelector:] () #2 0x000000019ac1d01c in -[NSTableView(NSTableViewViewBased) cancelOperation:] ()

I would like to avoid the middle man and call Objective C directly from C Currently I do this This is called from a dispatch table in a pure C file _ctx->mt_render_funcs.mtlEnd(_ctx); Which calls this routine in a obj c file .m void mtlEnd(MTRenderContext mt_ctx) { // Call the Objective-C method using Objective-C syntax [(__bridge id) mt_ctx->mt_render_funcs.mtlObj mtlEnd]; } Which ends up here... in ObjC #pragma mark mtlEnd (void)mtlEnd { // vertex buffer size_t size; size = sizeof(Vertex4ColorNormalTex) * _ctx->vert_eng.current_vertex; [_currentRenderEncoder setVertexBytes:_ctx->vert_eng.vertices length: size atIndex: VertexInputIndexVertices]; [_currentRenderEncoder drawPrimitives:(MTLPrimitiveType)_ctx->vert_eng.prim_type vertexStart:0 vertexCount:_ctx->vert_eng.current_vertex]; } It would simplify this to get rid of one call and call ObjC directly. The other idea is I want to use GCD and put a lock / unlock on the call from C to ensure thread safety so I can use GCD to dispatch a thread to do the ObjC routines. I want to stick with C as the foundation so it can be used directly from C or a FFI interface from other languages. But Metal works well in ObjC and I would prefer to use that. Thanks ahead of time.

I set the value of NSURLHasHiddenExtensionKey. I provide a textfield to rename a file and I set this flag based on whether the user has deleted or left on the path extension. So -setResourceValue:forKey:error: returns YES, does not populate the error, but does not honor the value I just set it to. I'm always setting it off the main thread on the same serial queue. Works the first time I rename the file then it just starts failing (silently). For example: NSError *setError = nil; if ([theURL setResourceValue:@(NO) forKey:NSURLHasHiddenExtensionKey error:&setError]) { [theURL removeAllCachedResourceValues]; NSNumber *freshRead = nil; NSError *getError = nil; if ([theURL getResourceValue:&freshRead forKey:NSURLHasHiddenExtensionKey error:&getError]) { if (freshRead.boolValue) { NSLog(@"it is yes when it should be NO."); } } if (getError != nil) { NSLog(@"Get error: %@",getError); } } if (setError != nil) { NSLog(@"Set error: %@",setError); } While I get that it is possible for there to be other apps setting this value at the same time as my app, doesn't really seem possible in my local environment right now. No errors log out but "it is yes when it should be NO." does log out.

So I'm reworking couple things in my app. And I noticed I had this old code that does the following: Creates a temporary directory. Writes a file in the temporary directory. After the file is written moves the file out of the temporary location and places it in its final destination. Okay so I was not creating the temporary directory using the recommended API. I was simply doing something like this: NSURL *tempDirectory = [NSURL fileURLWithPath:[NSTemporaryDirectory() stringByAppendingPathComponent:[NSProcessInfo processInfo].globallyUniqueString]]; // Create tempDirectory and write files inside it. Now I just changed the code to use the recommended API which takes the the volume of the target destination into account: -URLForDirectory:inDomain:appropriateForURL:create:error:) and I pass in NSItemReplacementDirectory and a url to appropriateForURL so the destination volume is taken into account. Now I have external storage mounted and I use the recommended approach. I discovered NSFileManager simply writes a directory right in a user facing location titled: **(A Document Being Saved By App Name) ** and the folder is not hidden. Is this intended behavior for this API? Are temporary files supposed to be user facing? I know it is good practice to clean up temporary stuff when you are done but in crashes or just forgetting to clean up will leave these behind which isn't the behavior I expect for "temporary files." Also if the user is viewing the folder in Finder they'll see these A Document Being Saved By App Name folders appear and disappear in the window as my app does this work.

Hello， We’re seeing an iPad-specific Launch Screen issue related to multitasking window sizes. Environment Device: iPad (iPadOS 26) Device orientation: Landscape App is launched in a small window where the app window is portrait-shaped (width < height) Issue When the iPad is in landscape but the app is launched as a portrait-shaped small window, the LaunchScreen.storyboard appears to be rendered/layouted as landscape, not matching the actual window geometry. As a result, the Launch Screen content is clipped / partially missing (we see blank/empty area at the bottom during launch). After the app finishes launching, our first view controller uses the correct window size and the UI looks fine — the problem is mainly during the Launch Screen phase. What we checked LaunchScreen.storyboard uses Auto Layout and is expected to adapt to screen/window size. This only reproduces when the device orientation and the app window aspect ratio don’t match (landscape device + portrait-shaped app window, or vice versa). When device orientation and window shape are aligned, the Launch Screen displays correctly. Question Is it expected that iPadOS renders LaunchScreen.storyboard based on the interface orientation / size class rather than the actual window bounds in multitasking scenarios? If not expected, what is the recommended way to ensure the Launch Screen matches the app’s actual window size/aspect ratio at launch (without using code, since Launch Screen is static)? Are there any additional diagnostics or recommended steps to help us investigate and confirm the root cause (e.g., specific logs, APIs/values to capture at launch such as UIWindowScene bounds, interfaceOrientation, size classes, or any guidance on how Launch Screen snapshots are chosen/cached in multitasking)? Thank you.

The documentation says: The caching behavior of the NSURL and CFURL APIs differ. For NSURL, all cached values (not temporary values) are automatically removed after each pass through the run loop. You only need to call the removeCachedResourceValueForKey: method when you want to clear the cache within a single execution of the run loop. The CFURL functions, on the other hand, do not automatically clear cached resource values. The client has complete control over the cache lifetimes, and you must use CFURLClearResourcePropertyCacheForKey or CFURLClearResourcePropertyCache to clear cached resource values. https://developer.apple.com/documentation/foundation/nsurl/removeallcachedresourcevalues()?language=objc Is this really true? In my experience I've had to explicitly remove cached resource values via -removeAllCachedResourceValues or removeCachedResourceValueForKey: otherwise the URL contains stale values. For example on a URL that no longer exists I attempted to read NSURLIsHiddenKey and the last value was already cached. Instead of getting a NSFileNoSuchFileError I get the old cache value unless explicitly call -removeCachedResourceValueForKey: first and I'm fairly certain the value was cached on a previous run loop churn.

When I appendAttributedString to [textView textStorage] it does not appear on the scrollable TextView. However when I NSLog the [textView textStorage] the Attributed string is outputted, and is therefore stored in the textView, see below. Occurs every time I ask to see the AttributedString I send to the textView. [textView textStorage] attributedString I need to see the attributedString displayed on the ScrollableTextView, but I don't know why I cannot see it.

Running print operation on WKWebView I hit EXC_BREAKPOINT and there is all kinds of console spew that looks concerning: ERROR: The NSPrintOperation view's frame was not initialized properly before knowsPageRange: returned. (WKPrintingView) ** CGContextClipToRect: invalid context 0x0. If you want to see the backtrace, please set CG_CONTEXT_SHOW_BACKTRACE environmental variable.** WebContent[7743] networkd_settings_read_from_file Sandbox is preventing this process from reading networkd settings file at "/Library/Preferences/com.apple.networkd.plist", please add an exception. CRASHSTRING: XPC_ERROR_CONNECTION_INVALID from launchservicesd CRASHSTRING: rdar://problem/28724618 Process unable to create connection because the sandbox denied the right to lookup com.apple.coreservices.launchservicesd and so this process cannot talk to launchservicesd. WebContent[7921] The sandbox in this process does not allow access to RunningBoard. Safe to ignore all this?

Hello, I'm trying to make a white-Label sort of thing for my app, that is: a script runs before the app launches, sets a certain LaunchAgent command that sets and environment variable, and based on that variable's value tha main app's icon changes to a certain logo (change only happens in the dock because changing the icon on disk breaks the signature) When the app launches it takes a noticeable time until the dock icon changes to what I want, so I worked around that by setting the app's plist property to hide the dock icon and then when the app is launched I call an objc++ function to display the icon in the dock again (this time it displays as the new icon) The showing happens through [NSApp setActivationPolicy:NSApplicationActivationPolicyRegular]; The problem happens when I try to close the app, it returns back to the old logo before closing which is what I want to prevent. I tried hiding the app dock icon before closing but even the hiding itself changes the icon before hiding The hiding happens through [NSApp setActivationPolicy:NSApplicationActivationPolicyProhibited]; My goal is that the main app icon doesn't appear to the user through the dock, and that the icon that is only visible is the other one that changes during runtime The reason for this is that I have an app that should be visible differently depending on an environment variable that I set using an installer app. The app is the same for all users with very minor UI adjustments depending on that env variable's value. So instead of creating different versions of the app I'd like to have just 1 version that adjusts differently depending on the env variable's value. Somehow this is the only step left to have a smooth experience Feel free to ask more clarification questions I'd be happy to help Thank you

I have (had) a view controller that does a bit of manual layout in a -viewDidLayout override. This was pretty easy to manage - however since introducing NSGlassEffectView into the view hierarchy I sometimes am getting hit with "Unable to simultaneously satisfy constraints" and Appkit would break a constraint to 'recover.' It appears translatesAutoresizingMaskIntoConstraints is creating some really weird fixed width and height constraints. Here I wasn't doing any autolayout - just add the glass view and set its frame in -viewDidLayout. At runtime since I do manual layout in -viewDidLayout the frames are fixed and there is no real "error" in my app in practice though I wanted to get rid of the constraint breaking warning being logged because I know Autolayout can be aggressive about 'correctness' who knows if they decide to throw and not catch in the future. In my perfect world I would probably just prefer a view.doesManualLayout = YES here - the subviews are big containers no labels so localization is not an issue for me. Rather than playing with autoresizing masks to get better translated constraints I decided to set translatesAutoresizingMaskIntoConstraints to NO and make the constraints myself. Now I get hit with the following exception: "The window has been marked as needing another Layout Window pass, but it has already had more Layout Window passes than there are views in the window" So this happens because the view which now has constraints -- I adjusted the frame of it one point in -viewDidLayout. My question is - is not legal to make changes in -viewDidLayout - which seems like the AppKit version of -viewDidLayoutSubviews. In UIKit I always thought it was fine to make changes in -viewDidLayoutSubviews to frames - even if constraints were used - this is a place where you could override things in complex layouts that cannot be easily described in constraints. But in AppKit if you touch certain frames in -viewDidLayout it can now cause this exception (also related: https://developer.apple.com/forums/thread/806471) I will change the constant of one of the constraints to account for the 1 point adjustment but my question still stands - is it not legal to touch frames in -viewDidLayout when autolayout constraints are used on that subview? It is (or at least was if I remember correctly) permitted to change the layout in -viewDidLayoutSubviews in UIKit but AppKit seems to be more aggressive in its checking for layout correctness). What about calling -sizeToFit on a control in viewDidLayout or some method that has side effect of invalidating layout in a non obvious way, is doing things like this now 'dangerous?' Shouldn't AppKit just block the layout from being invalidated from within -viewDidLayout - and leave whatever the layout is as is when viewDidLayout returns (thus making -viewDidLayout a useful place to override layout in the rare cases where you need a sledgehammer?)

Introduction: I’m encountering a consistent crash in production on iOS 26.2 (build 23C55). The crash occurs deep within libicucore when calling [NSDateFormatter dateFromString:]. Crash Summary: Exception Type: SIGSEGV (SEGV_ACCERR) Fault Address: 0xffffffff Thread: Crashed on Main Thread (Thread 0) Library: libicucore.A.dylib Code Snippet: The crash is triggered by the following method. It converts a string to an NSDate using a specific format and locale: // 获取日期date - (NSDate *)getDateWithTime:(NSString *)time formatter:(NSString *)formatterStr { NSDateFormatter *formatter = [[NSDateFormatter alloc] init]; [formatter setDateFormat:formatterStr]; formatter.timeZone = [NSTimeZone timeZoneWithName:@"Asia/Shanghai"]; formatter.locale = [[NSLocale alloc] initWithLocaleIdentifier:@"en_US_POSIX"]; return [formatter dateFromString:time]; } Backtrace: Here is the relevant part of the crash report: Incident Identifier: E24485B6-C53E-4115-A6CF-A7E4A952AD50 CrashReporter Key: 21FAC1CF-F56B-409A-98AA-351D3D2EB06C Hardware Model: iPhone18,2 Code Type: ARM-64 Parent Process: [1] Date/Time: 2026-01-12T01:32:25Z OS Version: iPhone OS 26.2 (23C55) Report Version: 105 SDK Version: 0.0.4 Exception Type: SIGSEGV Exception Codes: SEGV_ACCERR at 0xffffffff Crashed Thread: 0 Thread 0 Crashed: 0 libicucore.A.dylib 0x000000019b81def8 0x19b74a000 + 868088 1 libicucore.A.dylib 0x000000019b7da91c 0x19b74a000 + 592156 2 libicucore.A.dylib 0x000000019b8d8340 0x19b74a000 + 1631040 3 libicucore.A.dylib 0x000000019b8eae18 0x19b74a000 + 1707544 4 libicucore.A.dylib 0x000000019b8eb600 0x19b74a000 + 1709568 5 libicucore.A.dylib 0x000000019b878be4 0x19b74a000 + 1240036 6 libicucore.A.dylib 0x000000019b87ae84 0x19b74a000 + 1248900 7 libicucore.A.dylib 0x000000019b87b2dc 0x19b74a000 + 1250012 8 libicucore.A.dylib 0x000000019b9564ac 0x19b74a000 + 2147500 9 libicucore.A.dylib 0x000000019b954afc 0x19b74a000 + 2140924 10 libicucore.A.dylib 0x000000019b952794 0x19b74a000 + 2131860 11 libicucore.A.dylib 0x000000019b98689c 0x19b74a000 + 2345116 12 CoreFoundation 0x00000001895dbfe0 0x18953d000 + 651232 13 CoreFoundation 0x00000001895dbaa0 0x18953d000 + 649888 14 Foundation 0x0000000186d2029c 0x186b88000 + 1671836 15 Foundation 0x00000001874a62dc 0x186b88000 + 9560796 16 Foundation 0x00000001874a6384 0x186b88000 + 9560964 17 xxxx 0x0000000105ea6e30 -[xxxxx getDateWithTime:formatter:] + 168 and Thread 0 crashed with ARM-64 Thread State: pc: 0x000000019b81def8 fp: 0x000000016f96bc10 sp: 0x000000016f96bbd0 x0: 0x00000000ffffffff x1: 0x000000019ba1e8e0 x2: 0x0000000000000002 x3: 0x000000000000000b x4: 0x0000000000000074 x5: 0x0000000000000069 x6: 0x0000000000000000 x7: 0xfffff0003ffff800 x8: 0x000000009ba18014 x9: 0x00000001148dffd0 x10: 0x0000000000000002 x11: 0x0000000000000004 x12: 0x0000000000000220 x13: 0x0000000000000030 x14: 0x000000015b6f36b8 x15: 0x000000015cfe0000 x16: 0x00000002a19d0ff0 x17: 0x00000001f5590a70 x18: 0x0000000000000000 x19: 0x000000016f96bc30 x20: 0x0000000000000000 x21: 0x000000015cfe3200 x22: 0x000000019ba18014 x23: 0x0000000000000000 x24: 0x000000015cfe32a0 x25: 0x0000000000000003 x26: 0x0000000000000000 x27: 0x0000000000000000 x28: 0x000000015cfe3200 lr: 0x000000019b7da958 cpsr: 0x00000000a0000000

Hello, I'm currently working on an app that will have a different name (and UI) depending on an environment variable that is set by that app's custom installer that I also wrote. I'm trying to change the app name that is displayed in the menu bar (top left) programmatically. I've done some research and found that it's probably not possible to do so because it's fetched from the app's Info.plist The answer is probably already there but I'll ask the question: Is it possible to change the app's name in the menu bar without tampering with the Info.plist (as it will break the signature at runtime, and it can't be done at compile time) The use case here is that I'm shipping a single app with multiple installers, because the app will be the same for all sets of users but it will have minor UI changes (which in my opinion, don't need an entire separate release), the installers will set a flag that the app will, based on, change its UI to the corresponding set of users. For the most part it's been successful but only small issue remain like this one. The reason it's done like that is when updating I'll ship 1 release for all users to update rather than having to ship multiple releases with no difference between them

When I call this method on a thread that isn`t thread. And chose main thread check on target, The Console show the world : Main Thread Checker: UI API called on a background thread: -[UIApplication canOpenURL:] PID: 8818, TID: 10191278, Thread name: (none), Queue name: com.myqueue.canopen, QoS: 0 Backtrace: 4 TestDemo 0x0000000102f6c068 __39-[AppTools isExists:]_block_invoke_3 + 892 5 CoreFoundation 0x000000019e22995c 7519E999-1053-3367-B9D5-8844F6D3BDC6 + 1042780 6 CoreFoundation 0x000000019e12ec98 7519E999-1053-3367-B9D5-8844F6D3BDC6 + 15512 7 TestDemo 0x0000000102f6bba0 __39-[AppTools isExists:]_block_invoke_2 + 424 8 libdispatch.dylib 0x0000000103a4d7fc _dispatch_call_block_and_release + 24 9 libdispatch.dylib 0x0000000103a4ebd8 _dispatch_client_callout + 16 10 libdispatch.dylib 0x0000000103a55b48 _dispatch_lane_serial_drain + 744 11 libdispatch.dylib 0x0000000103a566e4 _dispatch_lane_invoke + 448 12 libdispatch.dylib 0x0000000103a61adc _dispatch_workloop_worker_thread + 1324 13 libsystem_pthread.dylib 0x000000019df72b88 _pthread_wqthread + 276 14 libsystem_pthread.dylib 0x000000019df75760 start_wqthread + 8

When trying to open an encrypted CoreML model file on a system with SIP disabled, the error message is Failed to generate key request for <...> with error: -42187 This should state that SIP is disabled and needs to be enabled.

This is a continuation of https://developer.apple.com/forums/thread/795348 I rambled too much and did not understand the underlaying problem. The problem is that I have a C function in a iOS library. I want to call this C function from a dylib that this library loads on runtime. When running directly from Xcode (either in debug or release mode) this works correctly. However, when the app is uploaded to testflight or distributed for debugging then the function is stripped and a null function pointer exception crashes the app. In the last post it was really hard to explain and I was pressed on time but I've created a minimal reproducible example: https://github.com/ospfranco/dylib_crash The instructions to run and reproduce the crash are on the README.

Hi, I have started facing an issue with Xcode since updating to macOS 26.1. The debugger is not stopping at breakpoints in Objective-C code, however breakpoints in Swift file are working fine. I am using Xcode 16.4. For breakpoints in Objective-C files I have started to get this message since the OS update - 'Xcode won't pause at this breakpoint because it has not been resolved.' I have already tried cleaning derived data and build folder. I do not want to upgrade to Xcode 26. Could someone help with the fix? Thanks

I am developing an iOS application that supports screen mirroring to Google TV (or Chromecast with Google TV). My goal is to mirror the iPhone/iPad screen in real time to a Google TV device. What I Have Tried So Far I have explored multiple approaches but haven't found a direct way to achieve low-latency screen mirroring. Here are some of my findings: Google Cast SDK: Google Cast SDK is primarily designed for casting media (videos, images, audio) rather than real-time mirroring. It supports custom receiver applications, but there are no direct APIs for full screen mirroring. Casting a recorded video is possible, but it introduces latency and is not real-time. ReplayKit for Screen Capture: RPScreenRecorder.shared().startCapture(handler: ...) allows capturing the iPhone screen as a video stream. However, sending this stream to Google TV in real time is a challenge. I could potentially encode the video as HLS and stream it, but the delay is significant. RTSP/UDP Streaming: Some third-party libraries support RTSP/UDP streaming for real-time screen sharing. Google TV does not natively support RTSP, making this approach difficult. My Questions: Is it possible to achieve real-time screen mirroring on Google TV using Google Cast SDK? Does Google TV support WebRTC or any low-latency streaming protocol that can be used from iOS? Are there any alternative approaches to mirror an iOS screen to Google TV with minimal latency? I would appreciate any guidance, code examples, or references to relevant documentation.

Hi all, when I launch my macOS app from Xcode 16 on ARM64, appKit logs me this error on the debug console: It's not legal to call -layoutSubtreeIfNeeded on a view which is already being laid out. If you are implementing the view's -layout method, you can call -[super layout] instead. Break on _NSDetectedLayoutRecursion(void) to debug. This will be logged only once. This may break in the future. _NSDetectedLayoutRecursion doesn't help a lot, giving me these assembly codes from a call to a subclassed window method that looks like this: -(void) setFrame:(NSRect)frameRect display:(BOOL)flag { if (!_frameLocked) [super setFrame:frameRect display:flag]; } I have no direct call to -layoutSubtreeIfNeeded from a -layout implementation in my codes. I have a few calls to this method from update methods, however even if I comment all of them, the error is still logged... Finally, apart from that log, I cannot observe any layout error when running the program. So I wonder if this error can be safely ignored? Thanks!