Xcode (starting from version 11, maybe) is buuuuuuuuuuuggy. It has big features, but fails miserably on small or tiny functionalities. You can try right-click the file and select "View As->Source Code". If this does not work either, then remove the file and re-add it back (at least this worked for me once or twice).

Anyway, I found out the cause. The error is thrown when initializing XMLDocument with an empty string: let xd = try XMLDocument(xmlString: "")

I have found where the Web entry is. I have to enable CloudKit service in project settings. Now I have another problem - I accidentally created several database containers (long time ago out of curiosity by clicking a button that says "Enable ClouldKit" or something similar). But I cannot find a way to delete the garbage items. The only way is to hide them in the CloudKit management Web UI.

Please ignore my question. It should be always like this because I set "Host Application" to None in the unit test target.

Ah, I found out why, though it's a little embarrassing... After so many years, I realized that NSApp.mainWindow is dynamic - it can be any window that has the key focus! I have to create a global variable to keep instance of the initial window (as designed in main storyboard). var mainWindow: NSWindow? // Set in MainWC.windowDidLoad class AnotherWC: NSWindowController, NSWindowDelegate { override func windowDidLoad() { super.windowDidLoad() print(self.className, #function) } func windowShouldClose(_ sender: NSWindow) -> Bool { print(self.className, #function) return true } func windowWillClose(_ notification: Notification) { print(self.className, #function) print(mainWindow ?? "mainWindow is nil") mainWindow?.orderFront(nil) } }

Maybe my question is too general. I have a need to calculate all width of an NSTableView. However, I found that total width of all columns is far less than NSTableView.bound.width: let width = tableView.tableColumns.reduce(0) { ac, col in ac + col.width } print(width, tableView.bounds.width) This is true even I manually adjust last column so that it fills the gap between the column and tableview right border. -----------| <- table right border last column| -----------| So I assume NSTableColumn.width and NSView.bounds.width are using different units.

At last, I found the answer myself, again. The answer lies in NSScroller.floatValue which inherited from NSControl. let shouldDelegate = { if let scroller = scrollView.verticalScroller { return scroller.isHidden || scroller.floatValue == 0 || scroller.floatValue == 1.0 } return true }()

I found a solution myself, after days of researching and experiments. It's related to another question "How tell if NSTableView is already displaying its last row entirely?". // For the inner tableview's scrollview class MyScrollView: NSScrollView { var onScrollWheel: EventHandler! override func scrollWheel(with event: NSEvent) { super.scrollWheel(with: event) // In onScrollWheel, determine if vertical scrollbar is hidden or at top/bottom, // then delegate this event to the outer tableview: // outerTableView.scrollWheel(with: event) onScrollWheel?(event) } }

I did much search on the web and found no answer. The only clue to my question is that I have use another "template" tableview that is identical to the inner tableview. Finally I devised a working solution, I posted here for the purpose of helping others who may have the same/similar problem. Note there is a little trick about calculating the actually row height - you have to include height of the template tableview's header view. func tableView(_ tableView: NSTableView, heightOfRow row: Int) -> CGFloat { if tableView is DetailsTableView { return tableView.rowHeight } if let rowHeight = rowHeights[row] { return rowHeight } let item = categorizedItems[row] if sizingTableView == nil { var objects: NSArray! detailsNib!.instantiate(withOwner: nil, topLevelObjects: &objects) for object in objects { if let sizingCellView = object as? DetailsCellView { sizingTableView = sizingCellView.tableView sizingTableView.delegate = self sizingTableView.dataSource = self sizingTableView.isHidden = true sizingTableView.enclosingScrollView?.setFrameSize(NSSize.zero) self.view.addSubview(sizingTableView) break } } } print("<", sizingTableView.bounds.height) sizingTableView.row = row sizingTableView.files = item.files sizingTableView.reloadData() print(">", sizingTableView.bounds.height) var rowHeight = sizingTableView.bounds.height + (sizingTableView.headerView?.bounds.height ?? 0.0) + summaryTableView.intercellSpacing.height rowHeights[row] = rowHeight if rowHeight > MaxRowHeight { let trailingHeight = (sizingTableView.bounds.height / Double(item.files.count)) * Double(TrailingRowCount) if rowHeight - MaxRowHeight < trailingHeight { // Try reserve height for some rows to let scrollbar look more natural. rowHeight = max(0, MaxRowHeight - trailingHeight) } else { rowHeight = MaxRowHeight } } return max(rowHeight, summaryTableView.rowHeight) }

Again, I found it myself. override func windowDidLoad() { super.windowDidLoad() window?.level = .floating }

I also have the same question here.

Finally I have to re-invent the wheel to solve this mysterious memory leak which I cannot control without the wheel. I am not sure if it is too bold to declare that NSData has serious problems with memory footprint, but... After I devised my own memory management facility (a smart buffer class), the memory footprint drops drastically and stops growing continuously. This is observed for several days.

It's strange. When I tried again, I found the file in /tmp: - (void)test { NSError* error; [@"abc123" writeToFile:@"/tmp/testfile" atomically:NO encoding:NSUTF8StringEncoding error:&error]; if (error) NSLog(@"%@", error); }

Yeah... I found it myself after 15 minutes of digging. It's right there under the "Assistant" menu item.

Great news for me and other individual developers! Broadcom acquired VMware.com and now VMware Workstation Pro/Fusion Pro are free for personal use.