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Can we decode twice in the same session with unarchiver?
In a class, I call the following (edited to simplify, but it matches the real case). If I do this: func getData() -> someClass? { _ = someURL.startAccessingSecurityScopedResource() if let data = NSData(contentsOf: someURL as URL) { do { let unarchiver = try NSKeyedUnarchiver(forReadingFrom: data as Data) print((unarchiver.decodeObject(of: [NSArray.self, someClass.self /* and few others*/], forKey: oneKey) as? someClass)?.aProperty) if let result = unarchiver.decodeObject(of: [NSArray.self, someClass.self /* same other types*/], forKey: oneKey) as? someClass { unarchiver.finishDecoding() print("unarchived success") return result } else { unarchiver.finishDecoding() print("unarchiving failed") return someClass() } } catch { return nil } } I get a failure on log : unarchiving failed But if I comment out the print(unarchiver.decodeObject) - line 8, it works and I get unarchived success // print((unarchiver.decodeObject(of: [NSArray.self, someClass.self /* and few others*/], forKey: oneKey) as? someClass)?.aProperty) However, when I do exactly the same for another class (I've compared line by line to be sure), it works even with the print statement. What could be happening here ?
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Jan ’26
Device Activity Reports are returning a blank screen in release mode
There is an inconsistent issue when views are rendered from the Device Activity Report Extension. This issue is noticeable only on release versions and it works fine in debug mode. Around 80% of the times, the Report Views return blank screen and this is only the case when a weekly/monthly filter is used. Although, it works as expected for daily report views. My questions are: How are all the Report Activity Views working fine in debug mode but not in release mode? How the daily activity filter works fine in the release mode but the weekly/monthly filters don't work? Is this because of a memory limit issue in the extension? As of now, I have the family-controls(distribution) entitlement only for the app and for the extensions I only have family-controls(development) entitlement. Do I need to request for family-controls(Distribution) entitlement even for the extensions? I have seen threads on the forum mentioning the blank screen issue associated with the DeviceActivityReport but haven't found a solution to it. Any suggestions/feedback would be of great help, thanks.
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1.5k
Jan ’26
NSURL - Are Cached Resource Values Really Automatically Removed After Each Pass Through the Run Loop?
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.
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Jan ’26
iOS app not getting killed after removing from app stack manually.
I am having an app in which we are using NEHotspotHelper to detect wifi changes. when I try to kill the app and network change detected, we are seeing logs in NEHotspotHelper* module and after that we are able see the logs indicating app launched in background. [Application] application(_:didFinishLaunchingWithOptions:), UIApplicationState: 2 But when I checked in the app stack, I couldn't find the app. Then I clicked icon to launch the app, it launched without splash screen as if it came from background. Need your support to understand this is expected behaviour.
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214
Jan ’26
App Logout / Termination Behavior When Changing Bluetooth Settings With and Without Multitasking
I would like to share an issue observed during app development. When changing Bluetooth settings from the system Settings app without using multitasking, the app does not terminate but instead logs the user out. However, when changing Bluetooth settings while using multitasking, the app terminates completely. In this context, I would like to understand: Whether there is any system behavior that causes the app to refresh or restart when Bluetooth settings are changed And why the app behavior differs in a multitasking environment, particularly in terms of app lifecycle handling Any insights into these behaviors would be greatly appreciated.
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Jan ’26
How to hide the NFC reading pop-up prompt?
Dear Apple Engineers, I am using NFCNDEFReaderSession to read information from NFC tags. When calling the begin method of the session, a system dialog/popover appears at the bottom of the screen. Is it possible to suppress or disable this dialog? Thank you for your assistance. Here is my demo code: @IBAction func beginScanning(_ sender: Any) { guard NFCNDEFReaderSession.readingAvailable else { let alertController = UIAlertController( title: "Scanning Not Supported", message: "This device doesn't support tag scanning.", preferredStyle: .alert ) alertController.addAction(UIAlertAction(title: "OK", style: .default, handler: nil)) self.present(alertController, animated: true, completion: nil) return } session = NFCNDEFReaderSession(delegate: self, queue: nil, invalidateAfterFirstRead: true) session?.alertMessage = "Hold your iPhone near the item to learn more about it. session?.begin() }
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Jan ’26
How does font caching / resources for each app work?
I'm a font developer. In the development process, I will revise a font and overwrite the OTF file that is currently enabled (registered) with macOS. If I then launch an app, it will immediately use the revised version of the font; while apps that are already loaded will continue to use the old version. This suggests that each app is loading new and separate font data, rather than getting it from some existing cache in memory. Yet macOS does have a "font cache" of some sort. Some apps, like TextEdit, seem to only load the fonts that they need to use. However, other apps, like Pages, load every enabled (registered) font on the OS!! (According to the Open Files list in Activity Monitor.) Given that /System/Library/Fonts/ is 625 Mb, and we can't disable any of it, isn't that a lot of data to be repeating? How many fonts is too many fonts? I can't find much documentation about the process.
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Jan ’26
Can I hide the NFC App Clip card?
Dear Apple Engineers: My app utilizes the App Clip experience. I would like to prevent the App Clip card from appearing when the host app is running in the foreground. How can this be achieved? I have observed that Alipay (in China) does not display an App Clip card when the device is tapped against a tag while the app is in the foreground, which indicates that this behavior is possible. Thank you for your assistance.
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Jan ’26
Array of Bool require NSNumber.self in NSKeyedArchiver decoding list of types
I decode an object with NSKeyedArchiver (SecureCoding): typealias BoolArray = Array<Array<Bool>> let val = decoder.decodeObject(of: NSArray.self, forKey: someKey) as? BoolArray I get the following log: *** -[NSKeyedUnarchiver validateAllowedClass:forKey:] allowed unarchiving safe plist type ''NSNumber' (0x204cdbeb8) [/System/Library/Frameworks/Foundation.framework]' for key 'NS.objects', even though it was not explicitly included in the client allowed classes set: '{( "'NSArray' (0x204cd5598) [/System/Library/Frameworks/CoreFoundation.framework]" )}'. This will be disallowed in the future. I changed by adding NSNumber.self in the list : let val = decoder.decodeObject(of: [NSArray.self, NSNumber.self], forKey: someKey) as? BoolArray No more warning in log. Is there a reason for this ?
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Jan ’26
How to solve this NSKeyedArchiver warning
I get several warnings in log: *** -[NSKeyedUnarchiver validateAllowedClass:forKey:] allowed unarchiving safe plist type ''NSNumber' (0x204cdbeb8) [/System/Library/Frameworks/Foundation.framework]' for key 'NS.objects', even though it was not explicitly included in the client allowed classes set: '{( "'NSArray' (0x204cd5598) [/System/Library/Frameworks/CoreFoundation.framework]" )}'. This will be disallowed in the future. I am not sure how to understand it: I have removed every NSNumber.self in the allowed lists for decode. To no avail, still get the avalanche of warnings. What is the key NS.objects about ? What may allowed classes set: '{( "'NSArray' be referring to ? An inclusion of NSArray.self in a list for decode ? The type of a property in a class ?
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Jan ’26
Can't get DeviceActivityReportExtension to work
DeviceActivityReportExtension issues Hi, I am currently working on a project and hoping to use DeviceActivityReportExtension. I have already successfully set up the DeviceActivityMonitorExtension and that is working correctly, but can't get this to reproduce. I initially had a complex capacitor project which displayed a native UI screen which (tried to) display the screen time report though it was failing silently. I tried a much simpler setup with a pure swift project (not an iOS dev so forgive my poor code quality) and still having an issue getting this to render on my computer. Here is a reproduction: https://github.com/ethanmichel0/screen-time-report-bug-recreation/tree/main Does this code work for others? and if not do you know how I can set this up? idk if my Xcode or iOS versions are incompatible (see versions in that link). Would be super grateful for some help, thanks so much.
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Jan ’26
How to call decoder with the right types ?
I have defined a class : class Item: NSObject, NSSecureCoding { var name : String = "" var color : ColorTag = .black // defined as enum ColorTag: Int var value : Int = 0 static var supportsSecureCoding: Bool { return true } Its decoder includes the following print statement to start: required init(coder decoder: NSCoder) { print(#function, "item should not be nil", decoder.decodeObject(of: Item.self, forKey: someKey))   Another class uses it: class AllItems: NSObject, NSSecureCoding { var allItems : [Item]? static var supportsSecureCoding: Bool { return true } and decodes as follows required init(coder decoder: NSCoder) { super.init() // Not sure it is necessary allItems = decoder.decodeObject(of: NSArray.self, forKey: mykey) as? [Item] print(#function, allItems) // <<-- get nil } I note: decoder returns nil at line 5 I have tried to change to decoder.decodeObject(of: [NSArray.self, NSString.self, NSColor.self, NSNumber.self], forKey: mykey)) Still get nil And, decoder of class Item is not called (no print in the log) What am I missing ?
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Jan ’26
App Logout / Termination Behavior When Changing Bluetooth Settings With and Without Multitasking
I would like to share an issue observed during app development. When changing Bluetooth settings from the system Settings app without using multitasking, the app does not terminate but instead logs the user out. However, when changing Bluetooth settings while using multitasking, the app terminates completely. In this context, I would like to understand: Whether there is any system behavior that causes the app to refresh or restart when Bluetooth settings are changed And why the app behavior differs in a multitasking environment, particularly in terms of app lifecycle handling Any insights into these behaviors would be greatly appreciated. “while using multitasking” means reducing the app’s size and displaying it side by side with the Settings screen at the same time. For better understanding, I will attach an image. Additionally, I found that YouTube also terminates when the “Allow Tracking” permission is changed in Settings while using the multitasking interface.
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Jan ’26
Crash (KERN_INVALID_ADDRESS) on IOS 26.2 GM when calling isEligibleForAgeFeatures
We recently released an update to our app to prepare for TX SB2420. Almost immediately on release, we started getting crash reports of crashes when calling isEligibleForAgeFeatures. Crashed: com.apple.root.user-initiated-qos.cooperative EXC_BAD_ACCESS KERN_INVALID_ADDRESS 0x0000000000000004 Is it possible that these are beta users that have IOS 26.2 RC or is there a bug in the release version of IOS 26.2? Note: The crash reports are coming from Crashlytics so we are not getting OS build identifiers other than version "26.2"
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Jan ’26
How to encode / decode Array < Array < SomeStruct > >
I need to encode and decode Array<Array> SomeStruct is multiplexed in an Int The former API did work: if let format = decoder.decodeObject(forKey: someKey) as? Array<Array<SomeStruct>> { } But using the new API if let format = decoder.decodeObject(of: Array<Array<Int>>.self, forKey: someKey) { generates an error: Cannot convert value of type 'Array<Array<Int>>.Type' to expected argument type '[AnyClass]' (aka 'Array<any AnyObject.Type>') encoding is done as follows: var format = Array(repeating: Array(repeating: 0, count: 4), count: 4) // initialize the var coder.encode(format, forKey: someKey) What is the correct syntax ?
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Jan ’26