Every time I insert a subclass (MYShapeLayer) into the model context, the app crashes with an error:
DesignerPlayground crashed due to fatalError in BackingData.swift at line 908. Never access a full future backing data - PersistentIdentifier(id: SwiftData.PersistentIdentifier.ID(backing: SwiftData.PersistentIdentifier.PersistentIdentifierBacking.managedObjectID(0xb2dbc55f3f4c57f2 <x-coredata://B1E3206B-40DE-4185-BC65-4540B4705B40/MYShapeLayer/p1>))) with Optional(A6CA4F89-107F-4A66-BC49-DD7DAC689F77)
struct ContentView: View {
@Environment(\.modelContext) private var modelContext
@Query private var designs: [MYDesign]
var layers: [MYLayer] {
designs.first?.layers ?? []
}
var body: some View {
NavigationStack {
List {
ForEach(layers) { layer in
Text(layer.description)
}
}
.onAppear {
let design = MYDesign(title: "My Design")
modelContext.insert(design)
try? modelContext.save()
}
.toolbar {
Menu("Add", systemImage: "plus") {
Button(action: addTextLayer) {
Text("Add Text Layer")
}
Button(action: addShapeLayer) {
Text("Add Shape Layer")
}
}
}
}
}
private func addTextLayer() {
if let design = designs.first {
let newLayer = MYLayer(order: layers.count, kind: .text)
newLayer.design = design
modelContext.insert(newLayer)
try? modelContext.save()
}
}
private func addShapeLayer() {
if let design = designs.first {
let newLayer = MYShapeLayer(shapeName: "Ellipse", order: layers.count)
newLayer.design = design
modelContext.insert(newLayer)
try? modelContext.save()
}
}
}
#Preview {
ContentView()
.modelContainer(for: [MYDesign.self, MYLayer.self, MYShapeLayer.self], inMemory: true)
}
@Model
final class MYDesign {
var title: String = ""
@Relationship(deleteRule: .cascade, inverse: \MYLayer.design)
var layers: [MYLayer] = []
init(title: String = "") {
self.title = title
}
}
@available(iOS 26.0, macOS 26.0, *)
@Model
class MYLayer {
var design: MYDesign!
var order: Int = 0
var title: String = ""
init(order: Int = 0, title: String = "New Layer") {
self.order = order
self.title = title
}
}
@available(iOS 26.0, macOS 26.0, *)
@Model
class MYShapeLayer: MYLayer {
var shapeName: String = ""
init(shapeName: String, order: Int = 0) {
self.shapeName = shapeName
super.init(order: order)
}
}
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In my application, I have NavigationStack presented as a sheet, and I intend to dynamically adjust its height while pushing views within it. I'm utilizing a global observable variable to manage the height and everything works fine except that the height changes abruptly without any animation. It abruptly transitions from one height to another.
The issue can be reproduced using the following code:
#Preview {
@Previewable @State var height: CGFloat = 200
Text("Parent View")
.sheet(isPresented: .constant(true)) {
NavigationStack {
Form {
NavigationLink("Button") {
RoundedRectangle(cornerRadius: 20)
.fill(Color.blue)
.frame(height: 200)
.navigationTitle("Child")
.onAppear {
withAnimation {
height = 300
}
}
}
}
.navigationTitle("Parent")
.navigationBarTitleDisplayMode(.inline)
.presentationDetents([.height(height)])
.onAppear {
withAnimation {
height = 150
}
}
}
}
}
As a mac user, I used to use the keyboard shortcut ⌘[ to go back to the previous page. However, and for unknown reason, the shortcut is not working while viewing the Apple Developer Forums, which is very annoying.
Is it possible to develop an iOS application that shows all of the user's photos in a custom view ?