Table Of ContentiOS 9 Swift Programming Cookbook
Vandad Nahavandipoor
iOS 9 Swift Programming Cookbook
by Vandad Nahavandipoor
Copyright © 2016 Vandad Nahavandipoor. All rights reserved.
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978-1-491-93669-6
[LSI]
Preface
When I started writing this edition of this book (which has been in the field and regularly
updated since iOS version 4), I thought to myself: what I should do to really overhaul it
and make it even more exciting than the previous editions? The answer was to rewrite the
whole book — every single word from scratch. Up to and including the iOS 8 Swift
Programming Cookbook (where I made the big switch from Objective-C to Swift) was to
base every edition on the previous edition. I would go through all the examples from the
previous edition to remove the ones that were irrelevant for the new edition or just
expendable because they were very simple and basic. I’d then update the remaining
examples to make sure they work great with the new iOS version. Then I would also write
new content for the new version of iOS. However, after 5 editions, I noticed that many
recipes were not really useful anymore and had stayed almost the same since the
beginning. So how could I solve this issue? The solution was to not do this any longer. I
had to write all new content, and that’s what I did for this book.
The amount of work that went into writing this book was tremendous, on my side and on
O’Reilly’s side. I have had to think long and hard about every new recipe, writing all the
example code anew and ensuring it works with the latest production tools from Apple.
You will learn a lot about Swift 2 and iOS 9 SDK in this book.
And yes, there is a great deal of watchOS material in this book. The chapter dedicated to
watchOS has more content in it than any other chapter. The reason behind that decision
was that watchOS was the main focus for this year’s WWDC and that Apple has paid
more attention to watchOS in iOS 9 SDK than to other frameworks or tools that they have
published this year. I hope you’ll enjoy writing watchOS apps as much as I do.
One last thing. Since Swift changes a lot and is constantly updated, please always check
the GitHub repo for this book to get the most up-to-date code. I have ensured that all code
compiles and works fine with Xcode 7 and the iOS 9 SDK, but if for some reason you are
on a beta Xcode that is newer than the production version of Xcode 7 that Apple has
released, do ensure that you have the latest code by checking out this book’s GitHub repo.
Have fun and I hope you’ll enjoy reading this book.
Audience
I assume that you are comfortable writing iOS apps, at least know your way around
Xcode, and can work with the simulator. This book is not for beginners. If you have never
programmed in Xcode before for iOS, it will be tough to learn iOS programming only
from this book. So I suggest that you complement your skills with other online resources.
The best market for this book is intermediate and advanced users.
I also assume that you have written a little bit of Swift code. In this book, I use Swift 2
and will teach you some of the concepts, but if you don’t know Swift, this is not the right
place to start. Please pick up Apple’s book on Swift programming first; try with that and
once you are a bit comfortable with Swift, come back to this book and I’m sure you’ll
learn a lot of new things, even about Swift 2.
Organization of This Book
Here I’ll explain what each chapter is about so that you’ll get a feeling for what this book
is going to teach you:
Chapter 1, Swift 2.0, Xcode 7, and Interface Builder
In this chapter, we go through a lot of new stuff in Swift, Xcode, and Interface
Builder (IB), such as the addition of the guard keyword to Swift and conditionally
extending types with Swift’s new runtime features. Swift has really matured with
Swift 2, and I want to share some of the most important additions with you.
Chapter 2, Apple Watch
This year’s WWDC star, without a doubt, is watchOS 2 with all its additions. Now
apps can run natively on the watchOS without having to talk to the iOS counterpart
app, and this is great for us. More work, more things to do, more fun. We will talk
about complications, transferring files between iOS and watchOS 2 apps,
downloading files right on the watch, recording audio, and playing multimedia on
your watch.
Chapter 3, The User Interface
Even though additions to UIKit were not talked about as extensively as watchOS 2 at
this year’s WWDC, there are still tons of new features that we can discuss, including
anchored constraints, stack views, and the new Safari view controller.
Chapter 4, Contacts
The all-new contacts APIs will be discussed in this chapter. The frameworks on
which this chapter is based are both completely new to iOS 9. With the APIs in these
frameworks, you’ll learn how to add new contacts to the user’s device, remove
contacts, edit them, or even allow the user to pick a contact from the list so that you
can perform your tasks on it.
Chapter 5, Extensions
Safari Content Blockers shocked a lot of developers during this year’s WWDC. This
allows us developers to create apps that get installed as extensions on the user’s
Safari browser, and allows us to block various elements of web pages that the user
views. For instance, you can now block pictures or various unwanted elements in the
websites that you specify in your app, and you can share these content blockers with
those who use your app. This chapter is all about new extension points that you can
add to your apps.
Chapter 6, Web and Search
Description:Additional Resources This book is not for beginners, so I assume you have already gotten a grip on Swift and can do basic things with it. Please read Apple’s
