It's always something. I decided I was done with the math book on Thursday. On Friday, I started thinking about Swift. It took me a day to get in the groove again updating a lot of Playgrounds from Swift2, and then the weekend and this morning to update SudokuBlocks to SudokuBlocks3.
I plan to do some write-ups on various Swift topics, but I probably will not update the Swift2 book.
The first write-up is not just an .md document but also an Xcode project. It describes how to make a Swift app with a custom view and a window controller, drawing on Hillegass and other stuff I've picked up. It shows how to communicate between the window controller, the view, and simple Swift classes in the project. It is quite simple, but may help someone, so that's why I'm publishing it.
It is on github here. The README tells the story, and the project is there as well.