Learning Swift: Building Apps for macOS, iOS, and Beyond

378 Pages·2018·16.18 MB·English

by  Jonathon Manning

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Learning
S wift
BUILDING APPS FOR macOS, iOS, AND BEYOND
Jonathon Manning,
Paris Buttfield-Addison & Tim Nugent

THIRD EDITION
Learning Swift
Building Apps for macOS, iOS, and Beyond
Jon Manning, Paris Buttfield-Addison, Tim Nugent
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Learning Swift
by Jonathon Manning, Paris Buttfield-Addison, and Tim Nugent
Copyright © 2018 Secret Lab. All rights reserved.
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March 2018: Third Edition
Revision History for the Third Edition
2018-03-26: First Release
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978-1-491-98757-5
[LSI]
Table of Contents
Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
Part I. Welcome to Swift
1. Getting Started. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Xcode 3
Getting Xcode 4
Creating Your First Project 4
Working with the Xcode Interface 6
The Editor 6
The Toolbar 8
The Navigator 10
Utilities 11
The Debug Area 13
Running Your Code 13
The iOS Simulator 14
Running on a Device 15
Distributing Your Apps 16
The Interface Builder 16
Interfaces in iOS 18
Conclusion 19
2. The Swift Programming Language. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
The Swift Language 22
Swift 3 Versus 4 24
Playgrounds and Swift 24
Comments 26
iii
Imports 27
Variables 27
Operators 30
Collections 31
Arrays 31
Tuples 32
Dictionaries 33
Control Flow 34
Loops 35
Switches 36
Types 39
Working with Strings 39
Sets 42
Enumerations 44
Type Safety and Conversion 46
Optionals 48
Type Casting 51
Functions and Closures 53
Using Functions as Variables 56
Closures 57
Convenience Features 59
The defer Keyword 59
The guard Keyword 60
Making Your Code Swifty 60
Conclusion 61
3. Object-Oriented Development in Swift. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Classes and Objects 63
Initialization and Deinitialization 64
Properties 66
Inheritance 69
Protocols 70
Extensions 72
Access Control 75
Operator Overloading and Custom Operators 78
Subscripts 80
Generics 81
Structures 82
Error Handling 84
Memory Management 87
Design Patterns in Swift 91
Model–View–Controller 92
iv | Table of Contents
Delegation 93
Swift Libraries 96
Structuring an App 97
Swift Package Manager 101
Conclusion 107
Part II. Building Selfiegram
4. Setting Up Our App. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Designing Selfiegram 112
Creating the Project 115
The Structure 118
Renaming the Views 120
5. Building the Model Object. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
The Selfie Object 123
The SelfieStore 127
Testing the SelfieStore 130
Filling Out the Method Stubs 136
6. Building the Selfie List UI. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Creating the Selfie List 145
Improving the Selfie List 151
7. Adding and Deleting Selfies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
Deleting Selfies 155
Taking New Selfies 157
8. Viewing and Editing Selfies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
The Selfie Viewer 165
Connecting the Code and the UI 167
Editing a Selfie 172
9. Adding Location Info to the Selfies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
Updating the Model 175
Testing Our New Model 178
Showing a Selfie’s Location 179
Expanding the Map 183
Determining Locations 186
Configuring the App to Support Location 186
Talking to the Location Hardware 188
Table of Contents | v
10. Building a Settings View. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
Building the Settings UI 193
Connecting the Settings into Our Hierarchy 195
Hooking Up the Settings 196
Implementing the Settings 197
11. Reminders and Notifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
Adding a Reminder to the Settings 201
Creating a Notification 203
Part III. Polishing Selfiegram
12. Theming and Sharing Selfiegram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Custom Fonts 214
Making the Theme 217
Sharing Selfies 221
Sharing from the Detail View Controller 222
Sharing from the List View Controller 224
13. Custom Views and View Controllers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
A Camera View 228
The Camera View Controller 231
Building the UI 231
Connecting the UI 234
Talking to the Camera 234
Calling the Capture View Controller 240
14. Image Overlays. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245
Creating the Overlay Model 245
Testing the Overlay Manager 252
Writing the Tests 252
Returning Available Overlays 255
Downloading Overlay Information 256
Downloading Overlay Images 258
15. Overlay UI. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263
Building the UI 263
Hooking Up the UI 266
Creating the Overlay View 266
Presenting the Overlays 268
Initial Setup 268
vi | Table of Contents
Drawing Eyebrows 271
Vision and Image Detection 274
Connecting It into the App 279
16. Localization and Internationalization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
Internationalization 284
Generating the String Table 286
Localization 287
Translating the Strings 290
Testing Locales 290
Pseudolanguages 292
Previewing Localizations 294
Conclusion 296
Part IV. Beyond Developing Selfiegram
17. Debugging. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299
The Debugger 299
Breakpoints 300
Inspecting Code 304
Controlling Program Flow 307
Performance 309
Instruments 310
18. UI Tests. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313
UI Testing Classes 313
Writing UI Tests 314
A Basic Test 314
Recording UI Actions 315
Checking if Elements Exist 318
Handling UI Interruptions 319
19. Automating Chores with Fastlane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321
The Fastlane Tools 322
Installing Fastlane 323
Installing via Homebrew 324
Installing via RubyGems 324
Installing via Direct Download 324
Setting Up a Project 324
Doing a Build 325
Configuring a Fastfile 327
Table of Contents | vii
20. Using Fastlane’s Tools. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329
Code Signing with match 329
The Problem That Match Solves 329
match’s Solution 332
Generating Screenshots Using snapshot 333
Using Boarding to Add Testers to TestFlight 337
Managing Your App’s Presence on the App Store Using deliver 339
Getting the Metadata 340
Submitting New Metadata 340
Looking Further 341
Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343
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