Nahavandipoor - IOS 11 Swift programming cookbook : solutions and examples for iOS apps

by Vandad Nahavandipoor

Copyright 2018 Vandad Nahavandipoor. All rights reserved.

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• December 2017: First Edition

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978-1-491-99247-0

[LSI]

Swift 4 is an incremental release of Swift: a tock in Apples usual tick-tock release cycle, where the tick is a major release and the tock is a follow-up release with bug fixes and some additions and improvements. Two of the biggest additions to Swift 4 are the Decodable and Encodable protocols, which together form the Codable protocol. These protocols allow you, with just a bit of configuration, to define, encode, and decode JSON objects, a task that you either previously did on your own or used a library to accomplish.

Another welcome addition to Swift is the ability to extend typed arrays. For instance, you can now add a function to arrays that contain Int instances, but not to any other arrays. This way you could, for instance, define a sum() function that returns the sum of all integers in the array. Such a function wouldnt make sense for an array of String objects, and therefore its best placed inside an extension to arrays that contain numeric data, such as an array of Int.

We all have had moments when we wished Xcodes source editor would be rewritten in order to properly function, and thats exactly what Apple has done with Xcode 9. We have a whole new state-of-the-art source editor with built-in GitHub integration. Xcode Server is also now built into Xcode itself, and you dont have to install macOS server in order to take advantage of it. We have a whole chapter dedicated to Xcode Server, so you will get to know it better soon.

The previous edition of this book focused primarily on whats new in iOS 10, but this version takes a more holistic look at iOS 11 and what can make a great iOS developer, including knowledge of continuous integration, snapshot testing, Swift 4, and Xcode 9.