Merge pull request #1242 from Esri/df/FFVLeakPatch

`FeatureFormView` - Various fixes

Author: dfeinzimer

Sources/ArcGISToolkit/Common/AttachmentPreview.swift

@@ -17,9 +17,6 @@ import SwiftUI
 
 /// A view displaying a list of attachments in a "carousel", with a thumbnail and title.
 struct AttachmentPreview: View {
-    /// An action which scrolls the Carousel to the front.
-    @Binding var scrollToNewAttachmentAction: (() -> Void)?
-    
     /// The name for the existing attachment being edited.
     @State private var currentAttachmentName = ""
 
@@ -47,6 +44,9 @@ struct AttachmentPreview: View {
     /// A Boolean value which determines if the attachment editing controls should be disabled.
     private let editControlsDisabled: Bool
 
+    /// The last locally added attachment.
+    private let lastAttachmentAdded: AttachmentModel?
+    
     /// The action to perform when the attachment is deleted.
     private let onDelete: (@MainActor (AttachmentModel) -> Void)?
 
@@ -59,30 +59,26 @@ struct AttachmentPreview: View {
     init(
         attachmentModels: [AttachmentModel],
         editControlsDisabled: Bool = true,
+        lastAttachmentAdded: AttachmentModel? = nil,
         onRename: (@MainActor (AttachmentModel, String) -> Void)? = nil,
         onDelete: (@MainActor (AttachmentModel) -> Void)? = nil,
-        proposedCellSize: CGSize,
-        scrollToNewAttachmentAction: Binding<(() -> Void)?>
+        proposedCellSize: CGSize
     ) {
         self.attachmentModels = attachmentModels
         self.proposedCellSize = proposedCellSize
         self.editControlsDisabled = editControlsDisabled
+        self.lastAttachmentAdded = lastAttachmentAdded
         self.onRename = onRename
         self.onDelete = onDelete
-        _scrollToNewAttachmentAction = scrollToNewAttachmentAction
     }
 
     var body: some View {
-        Carousel { computedCellSize, scrollToLeftAction in
-            Group {
-                makeCarouselContent(for: computedCellSize)
-                    .transition(.asymmetric(insertion: .slide, removal: .scale))
-            }
-            .onAppear {
-                scrollToNewAttachmentAction = scrollToLeftAction
-            }
+        Carousel { computedCellSize in
+            makeCarouselContent(for: computedCellSize)
+                .transition(.asymmetric(insertion: .slide, removal: .scale))
         }
         .cellBaseWidth(proposedCellSize.width)
+        .leftScrollTrigger(lastAttachmentAdded?.id)
     }
 
     /// - Note: Contextual actions are disabled for empty attachments as deletion and rename

Sources/ArcGISToolkit/Common/AttachmentsFeatureElementView.swift

@@ -34,10 +34,8 @@ struct AttachmentsFeatureElementView: View {
     /// A Boolean value indicating whether the input is editable.
     @State private var isEditable = false
 
-    /// Scrolls an ``AttachmentPreview`` to the front.
-    ///
-    /// Call this action when a new attachment is added to make it visible to the user.
-    @State private var scrollToNewAttachmentAction: (() -> Void)?
+    /// The last locally added attachment.
+    @State private var lastAttachmentAdded: AttachmentModel?
 
     /// A Boolean value denoting if the view should be shown as regular width.
     var isRegularWidth: Bool {
@@ -126,21 +124,21 @@ struct AttachmentsFeatureElementView: View {
             AttachmentPreview(
                 attachmentModels: attachmentModels,
                 editControlsDisabled: !isEditable,
+                lastAttachmentAdded: lastAttachmentAdded,
                 onRename: onRename,
                 onDelete: onDelete,
-                proposedCellSize: thumbnailSize,
-                scrollToNewAttachmentAction: $scrollToNewAttachmentAction
+                proposedCellSize: thumbnailSize
             )
         case .auto:
             Group {
                 if isRegularWidth {
                     AttachmentPreview(
                         attachmentModels: attachmentModels,
                         editControlsDisabled: !isEditable,
+                        lastAttachmentAdded: lastAttachmentAdded,
                         onRename: onRename,
                         onDelete: onDelete,
-                        proposedCellSize: thumbnailSize,
-                        scrollToNewAttachmentAction: $scrollToNewAttachmentAction
+                        proposedCellSize: thumbnailSize
                     )
                 } else {
                     AttachmentList(attachmentModels: attachmentModels)
@@ -176,7 +174,7 @@ struct AttachmentsFeatureElementView: View {
         models.insert(newModel, at: 0)
         withAnimation { attachmentModelsState = .initialized(models) }
         embeddedFeatureFormViewModel?.evaluateExpressions()
-        scrollToNewAttachmentAction?()
+        lastAttachmentAdded = newModel
     }
 
     /// Renames the attachment associated with the given model.

Sources/ArcGISToolkit/Components/FeatureFormView/InternalFeatureFormView.Model.swift renamed to Sources/ArcGISToolkit/Components/FeatureFormView/EmbeddedFeatureFormViewModel.swift

@@ -39,12 +39,14 @@ class EmbeddedFeatureFormViewModel {
     var visibleElements = [FormElement]()
 
     /// The expression evaluation task.
+    @ObservationIgnored
     private var evaluateTask: Task<Void, Never>?
 
     /// The feature form.
     private(set) var featureForm: FeatureForm
 
     /// The group of visibility tasks.
+    @ObservationIgnored
     private var isVisibleTasks = [Task<Void, Never>]()
 
     /// Initializes a form view model.
@@ -64,10 +66,13 @@ class EmbeddedFeatureFormViewModel {
     /// Kick off tasks to monitor `isVisible` for each element.
     @MainActor
     private func initializeIsVisibleTasks() {
+        isVisibleTasks.forEach { $0.cancel() }
+        isVisibleTasks.removeAll()
         for element in featureForm.elements {
-            let newTask = Task {
+            let newTask = Task { [weak self] in
                 for await _ in element.$isVisible {
-                    updateVisibleElements()
+                    guard !Task.isCancelled else { return }
+                    self?.updateVisibleElements()
                 }
             }
             isVisibleTasks.append(newTask)

Sources/ArcGISToolkit/Utility/Carousel.swift

@@ -22,10 +22,10 @@ struct Carousel<Content: View>: View {
     @State private var cellSize = CGSize.zero
 
     /// The identifier for the Carousel content.
-    @State private var contentIdentifier = UUID()
+    let contentIdentifier = UUID()
 
     /// The content shown in the Carousel.
-    let content: (_: CGSize, _: (() -> Void)?) -> Content
+    let content: (_: CGSize) -> Content
 
     /// The amount to offset the scroll indicator.
     let scrollIndicatorOffset = 10.0
@@ -39,9 +39,12 @@ struct Carousel<Content: View>: View {
     /// The fractional width of the partially visible cell.
     var cellVisiblePortion = 0.25
 
+    /// The trigger used to scroll the scroll view to content's leading anchor.
+    var leftScrollTrigger: (any Equatable & Hashable)?
+    
     /// A horizontally scrolling container to display a set of content.
     /// - Parameter content: A view builder that creates the content of this Carousel.
-    init(@ViewBuilder content: @escaping (_: CGSize, _: (() -> Void)?) -> Content) {
+    init(@ViewBuilder content: @escaping (_: CGSize) -> Content) {
         self.content = content
     }
 
@@ -87,17 +90,18 @@ struct Carousel<Content: View>: View {
 
     func makeCommonScrollViewContent(_ scrollViewProxy: ScrollViewProxy) -> some View {
         HStack(spacing: cellSpacing) {
-            content(cellSize) {
-                withAnimation {
-                    scrollViewProxy.scrollTo(contentIdentifier, anchor: .leading)
-                }
-            }
-            .id(contentIdentifier)
-            .frame(width: cellSize.width, height: cellSize.height)
-            .clipped()
             // Pad the content such that the scroll indicator appears beneath it
-            // so that the content is not covered. 
-            .padding(.bottom, scrollIndicatorOffset)
+            // so that the content is not covered.
+            content(cellSize)
+                .id(contentIdentifier)
+                .frame(width: cellSize.width, height: cellSize.height)
+                .clipped()
+                .padding(.bottom, scrollIndicatorOffset)
+                .onChange(of: leftScrollTrigger?.hashValue) {
+                    withAnimation {
+                        scrollViewProxy.scrollTo(contentIdentifier, anchor: .leading)
+                    }
+                }
         }
     }
 }
@@ -131,24 +135,30 @@ extension Carousel {
         copy.cellVisiblePortion = visiblePortion
         return copy
     }
+    
+    func leftScrollTrigger(_ trigger: (any Equatable & Hashable)?) -> Self {
+        var copy = self
+        copy.leftScrollTrigger = trigger
+        return copy
+    }
 }
 
 #Preview("cellBaseWidth(_:)") {
-    Carousel { _, _ in
+    Carousel { _ in
         PreviewContent()
     }
     .cellBaseWidth(75)
 }
 
 #Preview("cellSpacing(_:)") {
-    Carousel { _, _ in
+    Carousel { _ in
         PreviewContent()
     }
     .cellSpacing(2)
 }
 
 #Preview("cellVisiblePortion(_:)") {
-    Carousel { _, _ in
+    Carousel { _ in
         PreviewContent()
     }
     .cellVisiblePortion(0.5)
@@ -157,38 +167,30 @@ extension Carousel {
 #Preview("In a List") {
     List {
         Text(verbatim: "Hello")
-        Carousel { _, _ in
+        Carousel { _ in
             PreviewContent()
         }
         Text(verbatim: "World!")
     }
 }
 
-#Preview("Scroll to left action") {
-    struct ScrollDemo: View {
-        @State var scrollToLeftAction: (() -> Void)?
-        
-        var body: some View {
-            Carousel { _, scrollToLeftAction in
-                ForEach(1..<11) {
-                    Text($0.description)
-                        .id($0)
-                }
-                .onAppear {
-                    self.scrollToLeftAction = scrollToLeftAction
-                }
-            }
-            Button {
-                withAnimation {
-                    scrollToLeftAction?()
-                }
-            } label: {
-                Text(verbatim: "Scroll to left")
-            }
+#Preview("Programmatically scroll to left") {
+    @Previewable @State var items = [1]
+    
+    Carousel { _ in
+        ForEach(items, id: \.self) {
+            Text($0.description)
+                .id($0)
         }
     }
-    
-    return ScrollDemo()
+    .leftScrollTrigger(items)
+    Button {
+        items.insert(items.count + 1, at: 0)
+    } label: {
+        Text(verbatim: "Insert Item")
+    }
+    Text(verbatim: "The Carousel will scroll to the left to make the item visible, if needed.")
+        .foregroundStyle(.secondary)
 }
 
 private struct PreviewContent: View {