diff --git a/Proton/Sources/Swift/Table/TableCell.swift b/Proton/Sources/Swift/Table/TableCell.swift
index 3e66aafc..bbcfd388 100644
--- a/Proton/Sources/Swift/Table/TableCell.swift
+++ b/Proton/Sources/Swift/Table/TableCell.swift
@@ -49,6 +49,14 @@ public class TableCell {
public var onEditorInitialized: ((TableCell, EditorView) -> Void)?
+ @MainActor
+ private var retainCount = 0
+ /// Returns `true` if the cell has one or more retain invocations.
+ @MainActor
+ public var isRetained: Bool {
+ retainCount > 0
+ }
+
/// Additional attributes that can be stored on Cell to identify various aspects like Header, Numbered etc.
public var additionalAttributes: [String: Any] = [:]
@@ -184,6 +192,22 @@ public class TableCell {
contentView?.removeFocus()
}
+ /// Retains the cell to prevent it from getting recycled when viewport changes and cell is scrolled off-screen
+ /// Cell with focus is automatically retained and released.
+ /// - Note: A cell may be retained as many time as needed but needs to have a corresponding release for every retain.
+ /// Failing to release would mean that the cell will never participate in virtualization and will always be kept alive even when off-screen.
+ /// - Important: It is responsibility of consumer to ensure that the cells are correctly released after being retained.
+ @MainActor
+ public func retain() {
+ retainCount += 1
+ }
+
+ /// Releases a retained cell. Calling this function on a non-retained cell is a no-op.
+ @MainActor
+ public func release() {
+ retainCount = max(0, retainCount - 1)
+ }
+
func hideEditor() {
contentView?.hideEditor()
}
@@ -192,6 +216,7 @@ public class TableCell {
contentView?.showEditor()
}
+
func performWithoutChangingFirstResponder(_ closure: () -> Void) {
editor?.disableFirstResponder()
closure()
diff --git a/Proton/Sources/Swift/Table/TableView.swift b/Proton/Sources/Swift/Table/TableView.swift
index bbf756e4..5829c70d 100644
--- a/Proton/Sources/Swift/Table/TableView.swift
+++ b/Proton/Sources/Swift/Table/TableView.swift
@@ -412,8 +412,12 @@ public class TableView: UIView {
removeScrollObserver()
}
+ private var retainedCells = Set<TableCell>()
+
var cellsInViewport: [TableCell] = [] {
didSet {
+ reclaimReleasedCells()
+
guard oldValue != cellsInViewport else { return }
let oldCells = Set(oldValue)
@@ -422,16 +426,19 @@ public class TableView: UIView {
let toReclaim = oldCells.subtracting(newCells)
toReclaim.forEach { [weak self] cell in
- // Ignore reclaiming the cell if it has focus
- if cell.containsFirstResponder == false {
+ // Ignore reclaiming the cell if these are retained
+ // Cell having focus is always retained and released on lost focus
+ if cell.isRetained == false {
self?.repository.enqueue(cell: cell)
+ } else {
+ self?.retainedCells.insert(cell)
}
}
toGenerate.forEach { [weak self] cell in
- // Ignore generating the cell if it has focus. The focussed cell is not reclaimed, hence need not be regenerated.
- // In absence of this check, there may be cases where the focussed cell gets duplicated
- if cell.containsFirstResponder == false {
+ // Ignore generating the cell if it is already retained. The retained cell is not reclaimed, hence need not be regenerated.
+ // In absence of this check, there may be cases where the retained cell gets duplicated
+ if cell.isRetained == false {
self?.repository.dequeue(for: cell)
}
}
@@ -489,6 +496,15 @@ public class TableView: UIView {
.intersects(adjustedViewport) }
}
+ private func reclaimReleasedCells() {
+ retainedCells.forEach {
+ if $0.isRetained == false {
+ self.repository.enqueue(cell: $0)
+ retainedCells.remove($0)
+ }
+ }
+ }
+
func cellBelow(_ cell: TableCell) -> TableCell? {
guard let row = cell.rowSpan.max(),
let column = cell.columnSpan.min() else {
@@ -854,11 +870,13 @@ extension TableView: TableContentViewDelegate {
}
func tableContentView(_ tableContentView: TableContentView, didReceiveFocusAt range: NSRange, in cell: TableCell) {
+ cell.retain()
resetColumnResizingHandles(selectedCell: cell)
delegate?.tableView(self, didReceiveFocusAt: range, in: cell)
}
func tableContentView(_ tableContentView: TableContentView, didLoseFocusFrom range: NSRange, in cell: TableCell) {
+ cell.release()
removeSelectionBorders()
delegate?.tableView(self, didLoseFocusFrom: range, in: cell)
}
diff --git a/Proton/Tests/Table/TableViewAttachmentSnapshotTests.swift b/Proton/Tests/Table/TableViewAttachmentSnapshotTests.swift
index 3d4ebb5d..1766e8aa 100644
--- a/Proton/Tests/Table/TableViewAttachmentSnapshotTests.swift
+++ b/Proton/Tests/Table/TableViewAttachmentSnapshotTests.swift
@@ -1094,6 +1094,46 @@ class TableViewAttachmentSnapshotTests: SnapshotTestCase {
assertSnapshot(matching: viewController.view, as: .image, record: recordMode)
}
+ func FLAKY_testRecyclesRetainedCell() {
+ var viewport = CGRect(x: 0, y: 100, width: 350, height: 200)
+ delegate.viewport = viewport
+
+ Utility.drawRect(rect: viewport, color: .red, in: editor)
+
+ let attachment = AttachmentGenerator.makeTableViewAttachment(id: 1, numRows: 20, numColumns: 5)
+ attachment.view.delegate = delegate
+ editor.replaceCharacters(in: .zero, with: "Some text in editor")
+ editor.insertAttachment(in: editor.textEndRange, attachment: attachment)
+ editor.replaceCharacters(in: editor.textEndRange, with: "Text after grid")
+
+ XCTAssertEqual(attachment.view.containerAttachment, attachment)
+
+ viewController.render(size: CGSize(width: 400, height: 700))
+ assertSnapshot(matching: viewController.view, as: .image, record: recordMode)
+
+ let cell10 = attachment.view.cellAt(rowIndex: 1, columnIndex: 0)
+ cell10?.editor?.setFocus()
+
+ viewport = CGRect(x: 0, y: 300, width: 350, height: 200)
+ delegate.viewport = viewport
+ attachment.view.scrollViewDidScroll(editor.scrollView)
+
+ Utility.drawRect(rect: viewport, color: .red, in: editor)
+ viewController.render(size: CGSize(width: 400, height: 700))
+ assertSnapshot(matching: viewController.view, as: .image, record: recordMode)
+
+ let cell40 = attachment.view.cellAt(rowIndex: 4, columnIndex: 0)
+ cell40?.editor?.setFocus()
+
+ viewport = CGRect(x: 0, y: 320, width: 350, height: 200)
+ delegate.viewport = viewport
+ attachment.view.scrollViewDidScroll(editor.scrollView)
+
+ Utility.drawRect(rect: viewport, color: .red, in: editor)
+ viewController.render(size: CGSize(width: 400, height: 700))
+ assertSnapshot(matching: viewController.view, as: .image, record: recordMode)
+ }
+
func FLAKY_testPreventsRecyclingNestedEditorFocussedCell() {
var viewport = CGRect(x: 0, y: 100, width: 350, height: 200)
delegate.viewport = viewport
diff --git a/Proton/Tests/Table/__Snapshots__/TableViewAttachmentSnapshotTests/testRecyclesRetainedCell.1.png b/Proton/Tests/Table/__Snapshots__/TableViewAttachmentSnapshotTests/testRecyclesRetainedCell.1.png
new file mode 100644
index 00000000..922babf3
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diff --git a/Proton/Tests/Table/__Snapshots__/TableViewAttachmentSnapshotTests/testRecyclesRetainedCell.2.png b/Proton/Tests/Table/__Snapshots__/TableViewAttachmentSnapshotTests/testRecyclesRetainedCell.2.png
new file mode 100644
index 00000000..01398581
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diff --git a/Proton/Tests/Table/__Snapshots__/TableViewAttachmentSnapshotTests/testRecyclesRetainedCell.3.png b/Proton/Tests/Table/__Snapshots__/TableViewAttachmentSnapshotTests/testRecyclesRetainedCell.3.png
new file mode 100644
index 00000000..af5ed60c
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