iOS Apps for Masterminds: How to take advantage of Swift to create insanely great apps for iPhones and iPads

1289 Pages·2016·10.48 MB·English

by  J D Gauchat

iOS Apps

for Masterminds

How to take advantage of Swift

to create insanely great apps

for iPhones and iPads

J.D Gauchat

www.jdgauchat.com

Edited by: Gina Fusco

www.reword.ca

Cover Illustration by Patrice Garden

www.smartcreativz.com

iOS Apps for Masterminds

Copyright © 2016 by John D Gauchat

All Rights Reserved

No part of this work may be reproduced or transmitted in any form or by any
means, electronic or mechanical, including photocopying, recording, or by any
information storage or retrieval system without the prior written permission of

the copyright owner.

Companies, services, or product names used in this book are for identification

purposes only. All trademarks and registered trademarks are the property of their
respective owners. Apple™, iPhone™, iPad™ and iPod Touch™ are trademarks

of Apple Inc.

For information on translations, please visit www.formasterminds.com

The information in this book is distributed on an "as is" basis, without warranty.

Although every precaution has been taken in the preparation of this work,

neither the author nor Mink Books shall have any liability to any person or entity

with respect to any loss or damage caused or alleged to be caused directly or

indirectly by the information contained in this work.

The source code for this book is available at www.formasterminds.com

Registration Number: 1126232

1st Edition 2016 John D Gauchat

Table of Contents

INTRODUCTION
CHAPTER 1
1.1 Overview
Requirements. Mobile Operative Systems
1.2 Xcode
Running Xcode
1.3 Development
Programming Languages, Cocoa Touch API, Compiler
CHAPTER 2
2.1 Computer Programs
Playground
2.2 Variables
Memory, Primitive Types, Declaration and Initialization, Arithmetic Operators,
Constants
2.3 Data Types
Characters, Strings, Booleans, Optionals, Tuples
2.4 Collections
Arrays, Sets, Dictionaries
2.5 Conditionals and Loops
If and Else, Switch, While and Repeat While, For, For In, Control Transfer
Statements
2.6 Enumerations
Associated Values
CHAPTER 3
3.1 Programming Paradigms
3.2 Functions
Declaration of Functions, Standard Functions, Scopes, Closures
3.3 Structures
Definition of Structures, Methods, Initialization, Property Keywords, Computed
Properties, Type Properties and Methods, Primitive Type Structures and Casting,
String Structures, Array Structures, Set Structures, Dictionary Structures
3.4 Enumerations
3.5 Objects

Definition of Objects, Property Observers, Type Properties and Methods,
Optional Chaining, Reference Types, Memory Management, Inheritance, Type
Casting, AnyObject, Initialization, Deinitialization
3.6 Protocols
Definition of Protocols, Extensions, Delegates
CHAPTER 4
4.1 iOS SDK
Importing Frameworks
4.2 Foundation
More Standard Functions, Strings, Ranges, Numbers, Dates
4.3 Core Graphics
CGGeometry
4.4 UIKit
UIApplication, UIDevice, UIScreen, UIWindow, UIView, UIView Subclasses,
UILabel, UIProgressView, UIActivityIndicatorView, UIControl, UIButton,
UISegmentedControl, UISwitch, UISlider, UIStepper
CHAPTER 5
5.1 The Interface
Xcode Projects, Xcode Tools, Running the Project
5.2 Templates
MVC, Application Delegate, Storyboard, View Controllers
5.3 Interface Builder
Object Library, Guidelines, Properties
5.4 Connections
Outlets, Connections in the Storyboard, Actions, Outlet Collections, Real-Life
Application
CHAPTER 6
6.1 Adaptivity
6.2 Auto Layout
Constraints, Assigning Constraints, Editing Constraints, Standard Values,
Resolving Auto Layout Issues, Intrinsic Content Size, Multiple Views
Constraints, Relations and Priorities, Constraints in the Document Outline Panel,
NSLayoutConstraint, Real-Life Application
6.3 Size Classes
Grid, Adapting Constraints, Adapting Elements, Adapting Fonts,
UITraitCollection, Orientation, Previews
CHAPTER 7

7.1 Input and Output
UITextField, UITextView, Keyboard
CHAPTER 8
8.1 Images
UIImage and UIImageView, Visual Effects, Assets Catalog, Icons, Launching
Image
CHAPTER 9
9.1 Listing Values
UIPickerView, UIDatePicker
CHAPTER 10
10.1 NSTimer
CHAPTER 11
11.1 Scroll Views
Scrolling, Zooming, Pages, Scrolling the Interface
CHAPTER 12
12.1 Gesture Recognizers
CHAPTER 13
13.1 Multiple View Controllers
Segues, Unwind Segues, Segues in Code
13.2 Navigation Controllers
Navigation Controllers in the Storyboard, Navigation Bar, Items, Toolbar,
Custom Navigation, Orientation, Sharing Data
13.3 Tab Bar Controllers
Tabs, UITabBarController, Delegate, Real-Life Application
CHAPTER 14
14.1 Tables
UITableView, UITableViewCell, Table View Protocols, NSIndexPath,
Implementing Table Views, Selection, Sections and Indexes, Custom Cells, Self-
Sizing Cells
14.2 Table Views and Navigation Controllers
Adding Rows, Deleting Rows, Moving Rows
14.3 UITableViewController
Static Tables
14.4 Search
UISearchBar
CHAPTER 15

15.1 A Collection of Views
UICollectionView, UICollectionViewCell, UICollectionViewFlowLayout,
Collection View Protocols, Layout Protocol, Implementing Collection Views,
Scroll Direction, Selection
Supplementary Views, Flow Layout, Custom Layout, Real-Life Application
CHAPTER 16
16.1 Universal Container
UISplitViewController, UISplitViewControllerDelegate, Implementing Split
View Controllers
16.2 Improving the Interface
Item by Default, Detail View by Default, Display Mode Button, Split View
Controller Delegate
16.3 Expanding the Interface
Modal Views, UIPresentationController, UIPopoverPresentationController
CHAPTER 17
17.1 Alert Views
Alerts, Action Sheets
CHAPTER 18
18.1 Notification Center
System Notifications
18.2 Local Notifications
18.3 Key/Value Observing
KVC, KVO
CHAPTER 19
19.1 Errors
Throwing Errors, Handling Errors
CHAPTER 20
20.1 Queues
Operations, Main Queue
CHAPTER 21
21.1 User Preferences
NSUserDefaults
21.2 Files
NSFileManager, URLs and Paths, Files and Directories, Files Attributes, Files
Content, NSBundle
21.3 Archiving

Encoding and Decoding, Real-Life Application
CHAPTER 22
22.1 Custom Object Graph
Data Model, Core Data Stack, NSManagedObject, Managing Objects, Counting
Objects, Predicates, Sort Descriptors, Delete Objects
22.2 Fetched Results Controller
Sections, Search
22.3 Migration
CHAPTER 23
23.1 Data in the Cloud
Enabling iCloud, Testing Devices
23.2 Key/Value Storage
23.3 UIDocument
Multiple Documents
22.4 Core Data in iCloud
Seeding the Store, Duplicates
CHAPTER 24
24.1 Core Graphics
Destination, Context, Paths, Colors, Configuration, Saving the State, Clipping,
Gradients, Shadows, Transformations, Text, Images, Drawing Cycle, Image
Context
24.2 Core Animation
CALayer, 3D Transformations, CABasicAnimation, UIView Animations
CHAPTER 25
25.1 Video
AVAsset, AVPlayerItem, AVPlayer, AVPlayerLayer, CMTime, Video Player,
AVKit
25.2 Audio
AVAudioPlayerDelegate, Recording
25.3 Media
Media Controller, Query Media
CHAPTER 26
26.1 Image Picker Controller
Camera, Photos Library, Adapting the Controller, Storing Pictures, Modifying
Pictures
26.2 Custom Controllers

Camera, Photos, Videos
26.3 Core Image
CHAPTER 27
27.1 Links
27.2 Web Views
App Transport Security
27.3 Web Content
JSON, XML
27.4 Social Networks
UIActivityViewController, SLComposeViewController, SLRequest
CHAPTER 28
28.1 Contacts
Reading Contacts, Formatters, Working with Contacts,
CNContactViewController, CNContactPickerViewController
CHAPTER 29
29.1 Core Motion
Motion Device, Motion Activity, Pedometer, Altimeter
29.2 Core Location
Authorization, Getting the Location, Background Location, Region, Geocoding
CHAPTER 30
30.1 Map View
Configuring the Map, Annotations, User Location, Search, Directions
CHAPTER 31
31.1 Internationalization
Formatters, Languages, Translation, NSLocalizedString, Resources
CHAPTER 32
32.1 Publishing
Apple Developer Program, Certificates, Provisioning Profiles, and Identifiers,
iTunes Connect, Submitting the Application

Introduction

The first iPhone was regarded as a revolutionary piece of technology, but not for
the right reasons. At that moment, the innovation presented by this gadget was
clearly
changing
our
understanding
of
telecommunications
and
the

preconceptions we had of what a phone could do, but nobody, not even Apple,
was able to predict the impact that such an amazing piece of engineering would
have in the software industry.
At first, Apple's plan was to follow the trend. They wanted to provide a new
communication device with enhanced capabilities but under their strict control.
The device would be capable of running its own applications, also called apps or
native apps, but only those created by the company would be available. Each
user would have the same apps as everybody else and only access third-party
applications from the web and through the browser that was delivered with the
system. Apple was trying to focus its strategy on web applications and emerging
web technologies, like everybody else, but the incredible possibilities offered by
the iPhone inevitably altered its plans.
The innovations introduced by this powerful device caught developers'
attention all around the world, and the interest to create native applications grew
fast. Soon, methods to install unauthorized applications were created and
popularized. Dozens of third-party applications were developed and shared
through open markets online. The success of these first apps and the willingness
of users to install them (under the risk of damaging their devices) made clear that
not many people agreed with the company’s initial intentions. It was evident that
users preferred to tap on an icon and work with the app right away rather than
open a browser, remember a domain, type it, and wait for the web application to
load. These applications were easy to access, focused on a single purpose, and
visually more appealing than a website. Developers wanted to create and users
wanted to consume native apps.
This external pressure, along with internal demands from executives in
Apple’s headquarters, motivated a change in Steve Jobs’s mind, and the creation
of the App Store was announced. The creation of the App Store not only meant
that an official place to sell apps was going to be available, but also that a whole
set of tools was going to be provided by the company itself to create them. The
App Store and the iOS SDK (Software Development Kit) changed everything
for good. Developers now had the right tools to build their apps and users had a
safe place to buy them. Soon, thousands of native apps were available,

generating an excellent alternative to web applications and creating a whole new
market. The new apps attracted more customers for Apple’s devices, which
motivated the creation of more apps, in a positive spiral that generated billions of
dollars. Several applications created by developers working alone from their
bedrooms became an overnight success, triggering a gold rush, the effects of
which are still visible nowadays.
The new distribution channels and the production tools provided by Apple
have initiated a golden era for developers. The possibility and opportunities are
infinite. Native applications are here to stay, the market they have created is
growing by the day, and now you can be part of it.

IMPORTANT: Supporting links, examples, projects, videos, and resources
are available on our website: www.formasterminds.com. Apple's official
documentation is available at developer.apple.com.

Chapter 1
App Development

1.1 Overview

The decision to create the App Store and open the platform to developers was
not an easy one. Steve Jobs didn’t like the idea of exposing his highly praised
new creation to the same threats of personal computers. He didn’t want the bad
reputation his devices could get once affected by viruses or attacked by hackers.
He insisted on keeping the platform closed until he realized that they could take
advantage of the systems already developed by Apple for the iTunes Store to
stay in control of quality and sales. This decision didn’t come without a price for
developers. The system is open enough to allow full creativity, but it’s still under
Apple’s strict supervision, which means developers can only work according to
the company’s rules.

Requirements

Apple requires developers to use the software provided by the company to create
apps for its mobile devices. This software only works in Apple’s computers and
requires the developer to have an Apple account. For these reasons, the options
are very limited, but the good news is that most of the things we need are
provided for free.

Mac Computer—This in theory could be any Intel-based Mac computer,
but the development software always requires the latest operative system (OS
X), so in practice we need a relatively new computer.
Apple Developer Account—This is a basic account we can get for free; it
gives us access to the Member Center where we can watch videos, download
programming guides, read the official documentation, get sample codes, and
more.
Xcode—This is the software provided by Apple for development. The current
version is number 7. It’s free and the package comes with everything we need
to create our apps, including an editor, the SDK (Software Development Kit),
and a simulator to test the applications.
Apple Developer Program—This service is required to publish our apps
in the App Store and implement services like iCloud, so we will need to enrol
in this program as soon as our first app is ready for distribution. At this

moment the membership costs $99 US dollars per year.
Mobile Device—This could be any of the devices available in the market,
including iPads, iPhones, and iPods, but at the time of picking one for testing
we have to consider that old models don’t support the current versions of
Apple’s mobile operative system (iOS). Testing our applications in a real
device is highly recommended and necessary before publishing.

The setup is relatively simple. We have to get a Mac Computer capable of
running the operative system currently required by Xcode (at the time of this
writing, it is OS X 10.9), open an Apple developer account from
developer.apple.com using our personal Apple ID (the one that is created when
we initialized our computer), and install the latest version of Xcode (currently 7).
Xcode has everything we need, including a simulator to test mobile applications
on the computer. Once the applications are created, we have to enrol to the
Apple Developer Program to generate all the certificates and permissions we
need to submit our apps to the App Store and put them up for sale.

Mobile Operative Systems

iOS is the name of the operative system delivered by Apple with every mobile
device sold. The system is currently in version number 9. Applications
programed in the Swift language only work on systems from version 7, but this
doesn’t reduce or affect the potential market for these applications because most
devices are capable of updating their system to the latest one. At the time of this
writing, it is estimated that more than 90% of Apple devices in the market are
running iOS 8 or 9.

1.2 Xcode

Xcode is a general-purpose IDE (Integrated Development Environment). It
includes a very powerful editor with graphic tools to help us write our code, and
comes with the SDKs (Software Development Kits) for the creation of software
for the iOS and OS X operative systems. The SDKs include compilers for
Objective-C and the new Swift language. From Xcode, we can program software
for every Apple’s platform using any of these programming languages.

Xcode is available as an app on the Mac App Store. To download this

application, we have to open the App Store from Launchpad (the application
organizer that comes with OS X) or double click the App Store icon inside the
Applications folder in Finder (OS X’s file explorer). From the App Store, we
have to search for the term "Xcode". The window will show the Xcode’s icon at
the top (Figure 1-1, number 1). We have to click on the Free button to download
the software.

Figure 1-1: Xcode in the Mac App Store

Running Xcode

Once the downloading process is over, the software is automatically installed.
To open Xcode we have to go to Launchpad and click on the icon or search for
the program inside the Applications folder in Finder. Figure 1-2 shows Xcode's
welcome screen.