This was from an PM exchange I had last month while trying to help someone with LCB & FFI for JAVA / AndroidLCB wrapper for Apple's PDFKit but I'm a bit worried that I may be stepping on their toes since they include their own XPDF extension with their paid versions. I just needed to do some simple processing of a bunch of PDFs and wound up creating another LCB Library and Widget. It's a become a fairly complete wrapper and came together quickly, but I don't want to hurt their business either because as much as I'm complaining here, I do love their product and want them to do well as a business, and they all seem like very nice people too.
Since OpenSource LC Community Edition is no longer supported by LC Ltd, and it looks like LC 9.6.4 contains a cross platform widget wrapper for Google's PDFium library, that is now a rather moot point, perhaps even a complete waste of time.
So here is my incomplete LCB wrapper/widget for Apple's PDFKit for anyone still using LC Community Edition, tested with LCC 9.6.3 on macOS 10.14.6 & 10.15.7 (It might work on iOS too with some adjustments, I don't know ). I assume it will work with LC Commercial Editions as well although I don't know why you would want to.
If anyone is suddenly very interested in learning FFI + Objective C, this contains an example of using NSNotificationCenter in LCB.
There's two versions: the original LCB Library only ( that can create it's own viewing NSWindow) and a second version that's an Apple native PDFView in LC widget form that can be placed on your stacks. Theres some other functions like extracting text, page count etc.
I added the PDFviews because I wanted to see the PDFs I was extracting text from but the Browser Widget is tied to WebKit PDF plugin which apparently isn't fully compatible with Adobe's Acrobat WebPlug (which I need to have for my day job)