I've a custom UIView to render a large piece of text using CATiledLayers. My draw(rect:) implementation is quite simple: override func draw(_ rect: CGRect) { 	let range = layoutManager.glyphRange(forBoundingRect: rect, in: textContainer) 	layoutManager.drawBackground(forGlyphRange: range, at: .zero) 	layoutManager.drawGlyphs(forGlyphRange: range, at: .zero) } This code works without any issue on iOS 13, but fails with a crash on iOS 14 simulator: Thread 9: EXC_BAD_ACCESS (code=1, address=0x28) #0 0x00007fff2396a3f5 in _NSLayoutTreeMoveToGlyphIndex () I can see that draw(rect:) is being called from different threads in both iOS 13 and 14. However the EXC_BAD_ACCESS has never happened so far in iOS 13. I wonder whether this is a behaviour change in iOS 14 or an issue. If this is a change in NSLayoutManager, then is it still possible to use CATiledLayer to render large amount of text in coordination with NSLayoutManager?

In the "old" TextKit, page-based layout is accomplished by providing an array of NSTextContainers to NSLayoutManager, each with its own NSTextView. TextKit 2, NSTextLayoutManager allows only a single text container. Additionally, NSTextParagraph seems to be the only concrete NSTextElement class. Paragraphs often need to break across page boundaries. How would one implement page-based layout in TextKit 2?

I'm trying to implement custom NSTextContentManager and use it with NSTextView, however it seems that NSTextView expect NSTextContentStorage all the time. final class MyTextContentManager: NSTextContentManager { // ... } It's added to layout manager, and NSTextView instance finds it properly: let textContentManager = MyTextContentManager() textContentManager.addTextLayoutManager(textLayoutManager) however, when I use it, I see errors at: [MyTextContentManager textStorage]: unrecognized selector sent to instance 0x600003d84870 the textStorage property is part of NSTextStorageObserving, that is not NSTextContentManager interface. It looks like NSTextView is not ready to work with custom NSTextContentManager. What did I miss?

The way NSTextView is built it's inevitable to use NSTextStorage with TextKit2, however the NSAttributedString uses NSRange vs the TextKit2 family uses NSTextRange for text location, etc. What I struggle with is the relation between these two. I didn't find a convenient translation between these two. Is NSAttributedStrint NSRange length=1 equal to NSTextRange offset 1? I think it's not (at least it's not necessarily true for every NSTextContentManager. So my question is, given a NSTextRange, what is the corresponding NSRange in NSTextContentStorage.attributedString

I've been working with UITextView and TextKit 2, which became the default text engine since iOS 16, and I've encountered performance issues when handling very large text documents. Even on iPhone 14 Pro, I've noticed stuttering and frame drops when scrolling through the text view containing a large amount of text. To reproduce the issue, you can use the following code: // In iOS 16 let textView = UITextView() textView.text = "some really large string (say 1 million characters)" The scrolling performance in this scenario is not smooth. However, if you switch to TextKit 1 by accessing the layoutManager property, the performance significantly improves: // In iOS 16 let textView = UITextView() let _ = textView.layoutManager // this enables the compatibility mode textView.text = "some really large string (say 1 million characters)" With this code, scrolling remains smooth even with large text documents. It's very disappointing to see TextKit 2 performing worse than TextKit 1, even though Apple claims TextKit 2 has significantly improved performance with noncontiguous layout. Furthermore, the sample code for TextKit 2, available here, crashes when handling very large text due to excessive memory usage. Has anyone else experienced similar performance issues with TextKit 2, and are there any potential solutions or workarounds to improve the performance?

I am trying to add custom attributes on-the-fly. To make it work, I subclassed NSTextLayoutFragment, and overrode .textLineFragments property to return custom made NSTextLineFragment objects. But if I override it, TextKit2 no longer render the text and selection also doesn't work. It's same even if provide NSTextLineFragment with exactly same properties (attributed string and range). In WWDC 22 video, you told me that NSTextLayoutFragment and NSTextLineFragment are all immutable and have value semantics. But it doesn't work with different object, therefore seems still have very strong reference semantics. How to make it work with custom attributes? P.S. I also reported this as a feedback -- https://feedbackassistant.apple.com/feedback/12443016

Short version: Is it possible to do the expensive parts of setting UITextView attributedText on a background queue in advance of the UITextView main thread setup? Long version: Setting attributedText on UITextView is expensive, and UILabel is not an option for us. Is there a way to create a text container and layout manager ourselves in order to perform the expensive work on another queue in advance of setting up the UITextView? Ideally we wouldn’t need to have the layout manager draw a bitmap that we show instead of the UITextView altogether. We’re currently calling the layout manager’s ensureLayout(..) function on a background queue but not seeing an improvement in the main thread performance of setting the attributedText on the UITextView. Does ensureLayout(..) not compute and cache the layout work? Or is the layout work not the expensive part of setting attributed text?

Hey, Maybe someone can explain me why NSLayoutManager is giving me "unstable" layout? It's like it decides to include line-height-multiple of 1.2 sometimes: We're doing some custom text rendering and if I change font size by a bit (or other property), then suddenly there is this extra text spacing. What we noticed so far is that there is something special about the first font that was set on NSTextStorage, in that case text has no extra spacing. Once you change it to slightly modified font else - the extra spacing is introduced. It's not NSParagraphStyle.lineHeightMultiple - if I set it to something non default then it acts as extra, but doesn't solve the "layout instability" issue. Any clue what's causing this? or how to make it to be stable?

I am working on supporting some formatted text editing in my app, and I've been experimenting with copy and paste support for formatted text. I discovered that NSAttributedString implements NSItemProviderWriting, which means I can give it to UIPasteboard via setObjects and all the built-in attributes transfer perfectly if I then paste it into another text view, or even another app that behaves itself. But if I have custom attributes in my attributed string, having their values implement Codable doesn't let them transfer across the clipboard. In my implementation of textPasteConfigurationSupporting(_: transform:), I try to get an attributed string like this: let attr = item.itemProvider.loadObject(ofClass: NSAttributedString.self) { val, err in //...handle here } I get an error like this: Error Domain=NSItemProviderErrorDomain Code=-1000 "Cannot load representation of type com.apple.uikit.attributedstring" UserInfo={NSLocalizedDescription=Cannot load representation of type com.apple.uikit.attributedstring, NSUnderlyingError=0x600003e7bea0 {Error Domain=NSCocoaErrorDomain Code=260 "The file “b036c42113e34c2f9d9af14d6fefcbd534f627d6” couldn’t be opened because there is no such file." UserInfo={NSURL=file:///Users/username/Library/Developer/CoreSimulator/Devices/86E8BDD4-B6AA-4170-B0EB-57C74EC7DDF0/data/Library/Caches/com.apple.Pasteboard/eb77e5f8f043896faf63b5041f0fbd121db984dd/b036c42113e34c2f9d9af14d6fefcbd534f627d6, NSFilePath=/Users/username/Library/Developer/CoreSimulator/Devices/86E8BDD4-B6AA-4170-B0EB-57C74EC7DDF0/data/Library/Caches/com.apple.Pasteboard/eb77e5f8f043896faf63b5041f0fbd121db984dd/b036c42113e34c2f9d9af14d6fefcbd534f627d6, NSUnderlyingError=0x600003e7ac70 {Error Domain=NSPOSIXErrorDomain Code=2 "No such file or directory"}}}} But I tried making my custom attribute values implement NSSecureCoding, and then it worked. Why is Codable conformance not enough here? Is it because the code that serializes and deserializes is still in Objective-C and isn't aware of Codable? Will this change as the open-source Foundation in Swift work continues?

I'm working on an app displaying a few hundred custom labels. The custom label is modelled after UILabel. When I implement the custom label using TextKit, the app is using about 0.5 GB of memory. When I implement it using TextKit2, it takes about 1.2 GB. Did anyone notice such a big difference in memory usage between TextKit and TextKit2? For how long will TextKit be around before being deprecated?

If I set an exclusion path, e.g. in TextDocumentViewController.viewDidLoad() like: textLayoutManager.textContainer?.exclusionPaths = [bezierPath] I am getting a "Unexpectedly found nil while unwrapping an Optional value" crash in TextDocumentView.adjustViewportOffset() because viewportRange is nil on textViewportLayoutController. Setting an exclusion path also causes weird behavior for textLayoutManager.enumerateTextLayoutFragments() which refuses to iterate if the .ensuresLayout option is set. The problem happens in both iOS and macOS (though I only care about iOS). I'm able to get exclusionPaths to work fine if I use UITextView, but the performance is unworkable there. I also was able to set exclusionPaths in the STTextView project in GitHub, but I was unable to identify anything specific that code was doing differently. Anyone have ideas as to what else needs to happen to make exclusionPaths work?

When using NSTextLayoutManager.addRenderingAttribute(.backgroundColor, value: NSColor.red, for: range), the background color for a line is only drawn as far as the last visible character. There is also a thin space between the lines where the background color is not visible. Whe using NSLayoutManager.addTemporaryAttribute(.backgroundColor, value: NSColor.red, forCharacterRange: range), the background color is drawn also for newline characters and soft line wraps. I would like to achieve the effect of using NSLayoutManager.addTemporaryAttribute(.backgroundColor, value: NSColor.red, forCharacterRange: range), but since I'm targeting TextKit 2, I have to avoid using NSLayoutManager. Is there a way to achieve this with NSTextLayoutManager or one of the other related classes in TextKit 2?

Returning false from NSTextContentManagerDelegate.textContentManager(_:shouldEnumerate:options:) produces huge gaps in my layout instead of showing a continuous block of text. Instead of omiting the layout of the hidden element, there is a blank space that shows that appears to have the same size in layout as the omitted text element. Why is this happening and how can I prevent this? Example:

In this code sample, the TextDocumentView has a variable set to 5.0. Any idea where this 5.0 number is coming from? It is used internally in other calculations within TextDocumentLayer. While it works, I'm not sure what it signifies, and how to adapt it to our projects? Thanks

In macOS 14, NSAttributedString.Key.verticalGlyphForm has been deprecated. This key was previously used for rendering text vertically, particularly in languages like Chinese, Japanese, and Korean. I'm curious about the reasons behind its deprecation and would appreciate insights into alternative methods for displaying vertical text.

This function on NSTextLayoutManager has the following signature func enumerateTextSegments( in textRange: NSTextRange, type: NSTextLayoutManager.SegmentType, options: NSTextLayoutManager.SegmentOptions = [], using block: (NSTextRange?, CGRect, CGFloat, NSTextContainer) -> Bool ) The documentation here doesn't define what the CGRect and CGFloat passed to block are. However, looking at sample code Using TextKit2 To Interact With Text, they seem to be the frame for the textsegment and baselineposition respectively. But, the textSegmentFrame seems to start at origin.x = 5.0 when text is empty. Is this some starting offset for text segments? I don't seem to be able to find mention of this anywhere.

After upgrading to Sonoma and Xcode 15, some of the NSTextViews in my app no longer show up. However, if entering Debug View Hierarchy, you can see them just fine. This only seems to happen with certain views that are created programmatically.

This is a tricky one. I have a shipping product which, when compiled under Xcode 14.3.1 works as expected on Sonoma. If the same project is recompiled with Xcode 15, the subclass of NSTextView will not display correctly (text is same color as background). I am also using a custom NSLayoutManager (to draw invisibles). Unfortunately, there is an intermittent aspect to this. I use this subclass in several places and it works on my setup on the main editor, but not with some customers. Then I found a different use of the same subclass that does not work for me. When it does not work, it is consistent for that user. I have manually marked the textViews as using TextKit 1, with no change. I also tried the Clips Bounds to yes, again no change. If I change the class to NSTextView, the text displays properly, but I lose existing functionality. There appears to be some undocumented behavior change in Xcode 15 (or when linking against Sonoma SDK) that for subclasses of NSTextView (stored in XIB files). I know that there is a push to move toward TextKit 2, but it seems TextKit 1 support was possibly changed as well. The text is there and I can edit it, double click, copy and paste it, it is just invisible, when compiled with Xcode 15 (also 15.1). It has to be something very subtle that the subclassed TextView from one XIB will work, but from another XIB will not. Does anyone have any insight into the potential change with TextKit 1 implementation? Thanks.

I am interested in overriding the default find/replace dialog which comes up from the performFindPanelAction method. I want to add additional things you can search for like text color and text style/format. How would I go about doing this?

I have been getting crash reports from users of my Mac app on Sonoma 14.0 and 14.1 when typing into an NSTextView subclass. The crash logs I have show involvement of the spell-checking system - NSTestCheckingController, NSSpellChecker, and NSCorrectionPanel. The crash is because of an exception being thrown. The throwing method is either [NSString getParagraphStart:end:contentsEnd:forRange:] or [NSTextStorage ensureAttributesAreFixedInRange:]. I have not yet reproduced the crash. I have tried modifying the reference finding process to simply link every word, via NSStringEnumerationByWords. The text view in question recognizes certain things in the entered text and adds hyperlinks to the text while the user is typing. It re-parses and re-adds the links on every key press (via overriding the didChangeText method), on a background thread. From user reports, I have learned that: The crash only occurs on macOS 14.0 and 14.1, not on previous versions The call stack always involves the spell checker, and sometimes involves adding recognized links to the text storage (the call to DispatchQueue.main.async in the code below) The crash stops happening if the user turns off the system spell checker in System Settings -> Keyboard -> Edit on an Input Source -> Correct Spelling Automatically switch The crash does not happen when there are no links in the text view. Here is the relevant code: extension NSMutableAttributedString { func batchUpdates(_ updates: () -> ()) { self.beginEditing() updates() self.endEditing() } } class MyTextView : NSTextView { func didChangeText() { super.didChangeText() findReferences() } var parseToken: CancelationToken? = nil let parseQueue = DispatchQueue(label: "com.myapp.ref_parser") private func findReferences() { guard let storage = self.textStorage else { return } self.parseToken?.requestCancel() let token = CancelationToken() self.parseToken = token let text = storage.string self.parseQueue.async { if token.cancelRequested { return } let refs = RefParser.findReferences(inText: text, cancelationToken: token) DispatchQueue.main.async { if !token.cancelRequested { storage.batchUpdates { var linkRanges: [NSRange] = [] storage.enumerateAttribute(.link, in: NSRange(location: 0, length: storage.length)) { linkValue, linkRange, stop in if let linkUrl = linkValue as? NSURL { linkRanges.append(linkRange) } } for rng in linkRanges { storage.removeAttribute(.link, range: rng) } for r in refs { storage.addAttribute(.link, value: r.url, range: r.range) } } self.verseParseToken = nil } } } } } I've filed this as FB13306015 if any engineers see this. Can anyone