Learn Swift by building applications explore Swift programming through iOS app development

356 Pages·2018·18.623 MB·English

by  Atanasov, Emil

Learn Swift by Building
Applications
Explore Swift programming through iOS app development
Emil Atanasov
BIRMINGHAM - MUMBAI
Learn Swift by Building Applications
Copyright © 2018 Packt Publishing
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Graphics: Tania Dutta
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First published: May 2018
Production reference: 1230518
Published by Packt Publishing Ltd.
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ISBN 978-1-78646-392-0
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Contributors
About the author
Emil Atanasov is an IT consultant who has extensive experience with mobile technologies.
He started working in the field of mobile development in 2006. He runs his own contracting
and consulting company, serving clients from around the world Appose Studio Inc. He is
—
an MSc graduate from RWTH Aachen University, Germany, and Sofia University "St.
Kliment Ohridski", Bulgaria. He has been a contractor for several large companies in the US
and UK, serving variously as team leader, project manager, iOS developer, and Android
developer.
I want to thank my wife Elena, my family, and my friends for being very supportive, really
patient, and super cool. Thank you for keeping me motivated through the endless work
days. I know that in your eyes I'm a bizarre geeky person, who is spending most of the
time in the digital world. I appreciate your understanding.
About the reviewer
Giordano Scalzo is a developer with 20 years of programming experience, since the days of
ZXSpectrum. He has worked in C++, Java, .Net, Ruby, Python, and in a ton of other
languages that he has forgotten the names of. After years of backend development, over the
past 5 years, Giordano has developed extensively for iOS, releasing more than 20
apps apps that he wrote for clients, enterprise application, or on his own. Currently, he is
—
a contractor in London where, he delivers code for iOS through his company, Effective
Code Ltd, aiming at quality and reliability.
Id like to thank my better half, Valentina, who lovingly supports me in everything I do:
’
without you, none of this would have been possible.
Thanks to my bright future, Mattia and Luca, for giving me lots of smiles and hugs when I
needed them.
Finally, my gratitude goes to my mum and dad, who gave me curiosity and the support to
follow my passions, which began one day when they bought me a ZXSpectrum.
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Table of Contents
Preface
1
Chapter 1: Swift Basics – Variables and Functions
6
Variables
7
Optional types 12
Enumeration types
13
Basic flow statements
14
The if statements – how to control the code flow 14
Loops 15
The while loops 16
The switch statement 17
Functions
19
What is a tuple? 21
What is the guard statement? 23
How to tackle huge problems – bottom-up versus top-down 23
Summary
25
Chapter 2: Getting Familiar with Xcode and Playgrounds
26
Installing Xcode
26
Exploring Xcode
29
What do we see on the screen? 31
Toolbar 31
Menu 35
The Navigator panel (located to the left) 37
The Debug panel (located at the bottom) 38
The Utilities panel (located to the right) 39
Xcode preferences window 41
Playground
44
What is a playground? 44
Let's add some code 45
How to add auxiliary code to a playground 52
How to add resource to a playground 52
Converting a playground to a workspace 53
Markup in playgrounds 54
Different items in the markup language 54
Basic markup items 56
Summary
59
Chapter 3: Creating a Minimal Mobile App
60
Your first iOS application
61
Project structure 74
Table of Contents
AppDelegate 74
Application states 76
ViewController 77
Git 79
Summary
83
Chapter 4: Structures, Classes, and Inheritance
84
Structures and classes
84
Extensions 91
The deinit method 94
Type properties and functions 94
Adding custom data types to a playground 96
Inheritance
100
Base class 100
Class properties 103
Model-View-Controller (MVC) 104
Summary
108
Chapter 5: Adding Interactivity to Your First App
109
Storyboards
109
Visual components 111
Adding items to the storyboard 118
Linking the UI with the code 122
General discussion 138
Summary
139
Chapter 6: How to Use Data Structures, OOP, and Protocols
140
Primary collection types
140
Generics 141
Array 142
Set 144
Dictionary 148
How to choose the best collection type 150
List of items in a playground
151
UICollectionView 151
UICollectionViewCell 154
Reusing cells 157
Layouts 159
Table view in iOS app
163
Model list of cities 165
Displaying all cities 167
Adding search 172
Protocols
175
Protocols and inheritance 177
Summary
180
Chapter 7: Developing a Simple Weather App
181
[ ii ]
Table of Contents
Defining the app screens
182
The home screen 188
Favorite locations 192
Constraints 194
Picking a location 196
Model
198
Locations 207
Controllers and segues 212
The first segue 212
How to pass data 215
Passing information in the reverse direction 217
Defining a custom segue 218
Further improvements 219
Summary
220
Chapter 8: Introducing CocoaPods and Project Dependencies
221
Software – the modern way
222
Ruby and CocoaPods 223
How to use it 224
CocoaPods useful commands 228
Carthage
229
Swift Package Manager
230
Useful commands 231
Popular third-party libraries
237
Alamofire 238
Texture 239
RxSwift 240
Summary
241
Chapter 9: Improving a Version of a Weather App
242
Weather forecast API
243
What's an API? 243
List of requests 245
Creating new models 247
Pure network requests
250
Alamofire implementation 256
Improvements using third-party libraries 259
Better error handling 261
About the screen 263
Summary
267
Chapter 10: Building an Instagram-Like App
268
Tabbed app project
268
Firebase
269
Login 271
The different screens 278
[ iii ]
Table of Contents
Custom buttons on the tab bar 279
Creating a post 282
Models 288
Firebase 290
Filters 295
Summary
297
Chapter 11: Instagram-Like App Continued
298
Home screen
298
Profile screen
304
Search screen
312
Favorites screen
316
Polishing the home screen
318
Summary
330
Chapter 12: Contributing to an Open Source Project
331
Your account at GitHub
331
Forking a repository
332
Let's contribute
333
Pull request
335
Summary
338
Other Books You May Enjoy
340
Index
343
[ iv ]