Writing Swift Code

Abstract

Every iOS app needs a user interface, but that user interface won’t do anything until you write Swift code to make it work. While you could write all your code in a single file, it’s better to divide your code into files where each file contains related code. A simple app might only contain a handful of files, but a more complicated app could contain dozens or even hundreds of separate files that contain related Swift code. Within each file, you can further organize your Swift code into separate functions.