We are building a visionOS 26 app (deployment target visionOS 26.0). Inside a full immersive space, the user takes a spatial photo. The photo is shown on a RealityView attachment. We need the system share sheet( AirDrop, Messages, Mail, Copy, Save Image, and the item preview with Done) to appear when the user taps Share on that attachment.
The immersive space is:
ImmersiveSpace(id: "ImmersiveView") {
ImmersiveView()
}
.immersionStyle(selection: $panoImageView, in: .full)
.upperLimbVisibility(.visible)
The review UI is a RealityView attachment, not a window:
Attachment(id: "panoramaFrameCaptureReview") {
PanoramaFrameCaptureReviewView(model: frameCapture) {
guard let path = frameCapture.shareURL?.path else { return }
dismissWindow(id: "PanoramaPhotoShare")
Task { @MainActor in
try? await Task.sleep(nanoseconds: 180_000_000)
openWindow(id: "PanoramaPhotoShare", value: path)
}
}
}
The shared item is a stereo HEIC written with Image I/O (kCGImagePropertyGroupTypeStereoPair, left/right images, HEIF camera extrinsics and SimplifiedPinhole intrinsics). The same data displays correctly with ImagePresentationComponent and saves to Photos as a spatial photo. Share is the only part that fails.
Attempt 1. ShareLink on the attachment
Tapping Share does nothing. On entry to the immersive space the system logs:
Presentations are not currently supported in Immersive contexts.
Attempt 2. UIActivityViewController from the attachment’s hosting controller
let activity = UIActivityViewController(activityItems: [fileURL], applicationActivities: nil)
var presenter: UIViewController = self
while let parent = presenter.parent { presenter = parent }
presenter.present(activity, animated: true)
presenter is UIHostingController<RootView>. The console then says:
Skipping popover presentations transition, missing window or scene for <UIActivityViewController>.
Failed to request default share mode for fileURL:...heic error:Error Domain=NSOSStatusErrorDomain Code=-10814
No share UI appears. presentedViewController is non-nil, so a “did it present?” check does not detect the failure.
Attempt 3. A real WindowGroup whose only job is to present UIActivityViewController
WindowGroup(id: "PanoramaPhotoShare", for: String.self) { path in
if let path = path.wrappedValue {
PanoramaPhotoShareWindow(path: path)
}
}
.windowStyle(.plain)
.defaultSize(width: 20, height: 20)
.defaultWindowPlacement { _, _ in
WindowPlacement(.utilityPanel)
}
struct PanoramaPhotoShareWindow: View {
let path: String
@Environment(.dismissWindow) private var dismissWindow
var body: some View {
PanoramaPhotoSharePresenter(url: URL(fileURLWithPath: path)) {
dismissWindow(id: "PanoramaPhotoShare")
}
.frame(width: 8, height: 8)
.background(.clear)
}
}
final class PanoramaPhotoShareController: UIViewController {
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
guard view.window != nil, let url else { return }
let activity = UIActivityViewController(activityItems: [url], applicationActivities: nil)
activity.completionWithItemsHandler = { _, _, _, _ in self.onFinish?() }
present(activity, animated: true)
}
}
Tapping Share opens this window and the app crashes immediately. We removed the feature so users are not crashed. An earlier build that also put a ShareLink in that window logged:
Attempt to present <UIActivityViewController> on <UIHostingController<...PanoramaPhotoShareWindow...>> which is already presenting <UIActivityViewController>.
Question
What is the supported way, on visionOS 26, to present the system share sheet while a .full ImmersiveSpace stays open? If a window is required, how should that window present the sheet without crashing, and without showing a second window that only contains another Share button?
