TextEdit will happily trash an HTML file when you convert it to text – without any good reason, other than an engineer not being familiar with macOS.
AppKit
How to cater for Dark Mode when printing an AppKit view, and how to add a command to export a document in PDF format. Swift 5.0.
How can the Open Recent menu offer to open a document that no longer exists when the volume it was on is no longer mounted?
In Sierra but not Mojave, when the user opens an ancillary window, it appears for a moment, then vanishes. Is it a bug in the code, or in AppKit?
Would you like to have two or more windows open on the same document, so you can check notes or references while reading? Now you can, for PDFs.
A simple way to provide a proper Help book for your app, and separate PDF documentation without wasted effort. Uses Swift in Xcode.
By popular request, how to customise the PDF reader’s interface to enlarge the window and show larger thumbnails. With two lines of code.
This second part uses Xcode’s Interface Builder to create the document window, then wire it up to the code which brings PDFKit and AppKit together.
Building a useful app in Xcode 10.1 with Swift. This app is a PDF reader which requires around a dozen lines of code.
More bugs in Calculator and Activity Monitor when printing, dreadful lack of documentation of AppKit, TextKit, and CoreData. No wonder Apple is struggling to sell iPhones in China.
The Eclectic Light Company 