I'm watching the session video "What's new in Xcode 26" and when I try out the new #Playground macro (in the context of a local package in my project) I see only this activity indicator for about 10-15 minutes: Eventually I do see this error: Despite the error, my local package does not import SwiftUI and has no dependencies other than Foundation. I checked the Xcode 26 release notes and I don't see this issue mentioned. A clean build of my project takes 55 seconds. Is it expected behavior that #Playground would require 10+ minutes to spin up? Is there anything I can to do make the new #Playground macro work correctly? Thank you.

I recently added pushWindow to my app, and I discovered that in visionOS 26.2 RC (23N301), pushWindow followed by dismissWindow no longer works as expected. Specifically, if the user moves the pushed window, then when the pushed window is later dismissed, the parent window's position isn't aligned with the pushed window's new position. Its original position is restored instead. Curiously, the bug only happens when an app is launched from the visionOS home view, and not when an app is launched from Xcode. It also doesn't happen in the visionOS 26.2 simulator. Another interesting detail is that while the parent window is hidden, if the user long-presses the Digital Crown and then dismisses the pushed window, the parent window's position seems to be immune from the Digital Crown scene reorientation. It's restored to its original real world position. Demo video: https://youtu.be/zR3t2ON3Wz0 I've submitted feedback as FB21287011 with a sample app and detailed repro steps. Has anyone else encountered this issue already and figured out a workaround? It would be nice if I could get pushWindow to work correctly in my app. Thanks everybody! 😀

I posted https://developer.apple.com/forums/thread/809481 yesterday about an issue I discovered with pushWindow in visionOS 26.2 RC, but today I discovered a second problem with pushWindow. If window A calls pushWindow to present window B, and the user pins window B to a wall, the following unexpected behaviors are observed: Window B spontaneously disappears. If the user re-launches the (still running) app from the visionOS home view, both window A and window B appear simultaneously. I assume only window B should be visible at this point, since window A pushed window B. If the user closes window B, it's now impossible to present window B again. Calls to pushWindow appear to be ignored. If the user force-quits the app and relaunches it, and pushWindow is called again, window B appears, but window A remains visible. I also noticed this surprising behavior: This broken state of pushWindow behavior now affects all other apps on the system that may call pushWindow in the future, not just the app whose pushed window was pinned above. A workaround is to reboot the device, and then the system will behave as expected until the next time the user pins a pushed window.

I am creating an AR app that uses ARKit and SceneKit. Will visionOS support SceneKit AR applications, or will I have to rewrite my app using RealityKit? Thanks for answering my question. : - )

Hey everybody! Does anyone know if there's a UIKit API that's equivalent to SwiftUI's View/offset(z:)? https://developer.apple.com/documentation/swiftui/view/offset(z:) I'd like to translate a UIView forward in space a little bit on visionOS. ❤️

The WWDC24 video "Build a spatial drawing app with RealityKit" https://developer.apple.com/wwdc24/10104 at 12:04 includes a slide showing a Reality Composer Pro shader graph that features wonderful inline documentation comment boxes: Are shader graph inline comments a new feature that Reality Composer Pro supports? This would be extraordinarily useful, as complex shader graphs can be challenging to decipher. If so, how are inline shader graph comments created in Reality Composer Pro?

This question is about USD animations playing correctly in macOS Preview but not with RealityKit on visionOS. I have a USD file created with 3D Studio Max that contains mesh-based smoke animation: https://drive.google.com/file/d/1L7Jophgvw0u0USSv-_0fPGuCuJtapmzo/view (5.6 MB) Apple's macOS 14.5 Preview app is able to play the animation correctly: However, when a visionOS app uses RealityKit to load that same USD file in visionOS 2.0 beta 4, built with 16.0 beta 3 (16A5202i), and Entity/playAnimation is called, the animation does not play as expected: This same app is able to successfully play animation of a hierarchy of solid objects read from a different USD file. When I inspect the RealityKit entities loaded from the USD file, the ground plane entity is a ModelEntity, as expected, but the smoke entity type is Entity, with no associated geometry. Why is it that macOS Preview can play the animation in the file, but RealityKit cannot? Thank you for considering this question.

I've created a minimal iOS RealityKit/ARKit app with only this view controller: import UIKit import RealityKit import ARKit class ViewController: UIViewController { var arView: ARView! override func viewDidLoad() { super.viewDidLoad() arView = ARView(frame: view.bounds, cameraMode: .nonAR, automaticallyConfigureSession: true) arView.autoresizingMask = [.flexibleWidth, .flexibleHeight] view.addSubview(arView) } } When I run this app in the iOS 18.1 simulator using Xcode 16.1 beta 2 (16B5014f), RealityKit logs the warnings included below to the console. I see similar warnings on the device, running iOS 18.0. Should I be concerned about any of these warnings? Please let me know if I should submit feedback reporting this issue. Thank you. Could not locate file 'default-binaryarchive.metallib' in bundle. Registering library (/Library/Developer/CoreSimulator/Volumes/iOS_22B5045f/Library/Developer/CoreSimulator/Profiles/Runtimes/iOS 18.1.simruntime/Contents/Resources/RuntimeRoot/System/Library/PrivateFrameworks/CoreRE.framework/default.metallib) that already exists in shader manager. Library will be overwritten. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/suFeatheringCreateMergedOcclusionMask.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arKitPassthrough.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arSegmentationComposite.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arInPlacePostProcessCombinedPermute0.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arInPlacePostProcessCombinedPermute1.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arInPlacePostProcessCombinedPermute2.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arInPlacePostProcessCombinedPermute3.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arInPlacePostProcessCombinedPermute4.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arInPlacePostProcessCombinedPermute5.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arInPlacePostProcessCombinedPermute6.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arInPlacePostProcessCombinedPermute7.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arInPlacePostProcessCombinedPermute8.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arInPlacePostProcessCombinedPermute9.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arInPlacePostProcessCombinedPermute10.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arInPlacePostProcessCombinedPermute11.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. Could not resolve material name 'engine:BuiltinRenderGraphResources/AR/arInPlacePostProcessCombinedPermute12.rematerial' in bundle at '/Users/drew/Library/Developer/CoreSimulator/Devices/6BCC578D-5046-49E6-B149-390576C7241D/data/Containers/Bundle/Application/75E15C63-F1D2-487F-A057-EBA2D45582C3/ARViewFailApp.app'. Loading via asset path. ... Compiler failed to build request makeRenderPipelineState failed [reading from a rendertarget is not supported]. Pipeline for technique meshShadowCasterProgrammableBlending failed compilation!

For a UIKit app based on scenes (UIScene), is it safe to reference UserDefaults in code that is executed from UIApplicationDelegate/application(_: didFinishLaunchingWithOptions:) ? I've read that in iOS 15, there were undocumented scenarios involving app prewarming that would cause UserDefaults reads to fail within a window of time after device reboots, as described at https://christianselig.com/2024/10/beware-userdefaults/ The failure mode is that an app would be released, and months later, a small fraction of users would report failures consistent with UserDefaults reads unexpectedly returning nil, causing a loss of data. The user experience is bad, and debugging this behavior is then challenging because of how rarely it occurs. Apple's https://developer.apple.com/documentation/uikit/app_and_environment/responding_to_the_launch_of_your_app/about_the_app_launch_sequence#3894431 seems to suggest that prewarming only executes an app "up until, but not including when main() calls UIApplicationMain(_:_:_:_:), but https://stackoverflow.com/questions/71025205/ios-15-prewarming-causing-appwilllaunch-method-when-prewarm-is-done documents that UIApplicationDelegate/application(_: didFinishLaunchingWithOptions:) has in fact been observed executing during app prewarming in scene-based apps. So, my question: In an app based on scenes, if I'd like to reference UserDefaults within UIApplicationDelegate/application(_: didFinishLaunchingWithOptions:), when is it safe to do this? I'm guessing the answer is one of these: Never. Only in apps that don't support scenes. Only in iOS 16 or later. Only in IOS 17 or later. Is it guaranteed safe to reference UserDefaults in UIWindowSceneDelegate/scene(_:willConnectTo:options:) or later? Is there documentation from Apple regarding this issue? Thank you.

In Xcode 16, when I use File > New > Project to create a new iOS app project, Xcode automatically creates an asset catalog file called Assets.xcassets in the project. However, if I later use File > New > File from Template, for example to add an asset catalog to an embedded Swift package within a project, Xcode suggests the default filename Media.xcassets for the file, instead of Assets.xcassets. Why is the default name for this file different in each context? Thank you for explaining this troubling consistency issue which causes me to lie awake at night.

Starting with iOS 18.0 beta 1, I've noticed that RealityKit frequently crashes in the simulator when an app launches and presents an ARView. I was able to create a small sample app with repro steps that demonstrates the issue, and I've submitted feedback: FB16144085 I've included a crash log with the feedback. If possible, I'd appreciate it if an Apple engineer could investigate and suggest a workaround. It's awkward to be restricted to the iOS 17 simulator, which does not exhibit this behavior. Please let me know if there's anything I can do to help. Thank you.

In Xcode, when you type a word like "don't", a second apostrophe is automatically inserted after the word and you have to manually delete it. Repro steps: Create a new empty Markdown file or XML file. Open the file in Xcode. Type the word “don’t”. Expected behavior: The word “don’t” appears. Observed behavior: The word “don’t” appears, followed by an extra single quote.

In Reality Composer Pro 2.0 (448.120.2), if I use the "Create new scene in the project" button more than once, this feature doesn't seem to work. The second time I use "Create new scene in the project", Reality Composer Pro displays a new empty USDA file in the project browser with the wrong icon (a yellow document icon instead of a 3D box icon). Also, it doesn't create the new scene's USDA file on disk or display the scene in entity hierarchy browser or create a new tab. Consequently, whenever I want to add more than one new scene to my project, I have to repeatedly quit and restart Reality Composer Pro. In my use of RCP just now, I had to quit and restart RCP six times to create seven new scenes. Is this a known issue? Repro steps: In a Reality Composer Pro project, create a new folder using the "add folder" icon button in the project browser. Inside the new folder, click the "Create new scene in the project" icon button. Click the "Create new scene in the project" icon button a second time. Expected behavior: A new USDA file is created on disk. The new USDA file's root entity appears in the entity hierarchy browser and a corresponding new tab is created. Observed behavior: The USDA file for this scene is not created on disk and it does not appear in the entity hierarchy browser in a new tab. In the project browser view, a yellow document icon appears and it does not appear to correspond to an actual USDA file. Thank you for any insight you can provide about this issue.

Liquid Glass was introduced as a universal design language for all platforms, but isn't supported by visionOS 26 beta. For a small team creating a visionOS app targeted for release in fall 2026, should we focus our design work on Liquid Glass, or for the existing visionOS design language?

We're using RealityKit to create a science education AR app for iOS, iPadOS, and visionOS. In the WWDC25 session video "Bring your SceneKit project to RealityKit" https://developer.apple.com/videos/play/wwdc2025/288 at 8:15, it's explained that when using RealityKit, RealityView should be used in all cases, whereas in the past, SceneKit required SCNView, SceneView, or ARSCNView, depending on an app's requirements. Because the initial development of our app on iOS predates iOS 18's RealityView, our app currently uses ARView to render RealityKit AR content on iOS and iPadOS. Is it recommended that we migrate to RealityView, or can we safely continue using our existing ARView implementation? We'd prefer to avoid unnecessary development cost. If migrating from ARView to RealityView is recommended, what specific benefits should we expect from this transition? Thank you.