beginning ios programming for dummies

Rajiv Ramnath, PhD is Associate Professor of Practice in computer

science and engineering and Director of Practice at the Collaborative

for Enterprise Transformation and Innovation at The Ohio State

University. Before that, he worked in industry, leading research and

commercial product development .

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9 781118 799277

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ISBN:978-1-118-79927-7

Open the book and find:

• The basics of object-oriented

programming

• How to use patterns and

frameworks

• Details on setting up the Xcode

Development Environment

• Examples to help you do

object-oriented iOS app design

• How to make your apps fast

and responsive

• Information on designing

user-friendly apps

• How to publish to the App Store

• Ten developer resources for iOS

Programming Languages/iOS

Get coding today with this useful

guide to creating iOS apps

Apple’s iOS is everywhere, thanks to the iPhone, iPad, and other

devices. If you’ve always wanted to be an iOS programming

rock star, this great resource is the guide for you. Discover iOS

programming, including how to get your apps into Apple’s

famous App Store and the best way to make applications that

users will be clamoring to download.

• iOS is everywhere — get started with creating apps forthis highly

popular mobile operating system

• Meeting the methods and platforms — take your object-oriented

programming to the next level with the Xcode Development

Environment

• Making youriOS apps great — make user-friendly apps that are

fast, responsive, complete,robust,reliable, and secure

• Connecting your apps — publish your apps in the App Store

and become an iOS programming star

• Study up — use a long list ofresources to find out more about

object-oriented and iOS programming

Beginning iOS Programming

Ramnath

Rajiv Ramnath, PhD

Author of Android 3 SDK Programming

For Dummies

Learn to:

• Program in the iOS environment using

Xcode® and Cocoa® frameworks

• Create simple interfaces

• Work with libraries, storyboards,

arrays, structures, functions,

and pointers

• Use simulators for testing and

development

Beginning

iOS Programming

Making Everything Easier!™

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Cheyney Loffing

Beginning iOS

Programming

Beginning iOS Programming For Dummies®

Published by: John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030-5774, www.wiley.com

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Library of Congress Control Number: 2013954213

ISBN 978-1-118-79927--7 (pbk); ISBN 978-1-118-79931-4 (ebk); ISBN 978-1-118-79932-1 (ebk)

Manufactured in the United States of America

10 9 8 7 6 5 4 3 2 1

Contents at a Glance

Introduction ................................................................ 1

Part I: Getting Started with iOS Programming................ 5

Chapter 1: Entering Mobile Application Development .................................................7

Chapter 2: Object-Oriented Design Principles .............................................................25

Chapter 3: Effectively Using Objective-C......................................................................55

Part II: Meeting the Methods and Platforms................. 89

Chapter 4: Patterns and Frameworks............................................................................91

Chapter 5: Setting Up to Develop iOS Apps................................................................113

Chapter 6: Developing an App on iOS .........................................................................135

Chapter 7: Illustrating Object-Oriented iOS App Design...........................................173

Part III: Making Your iOS Apps Fit for Consumption... 207

Chapter 8: Effectively Using Xcode..............................................................................209

Chapter 9: Developing Your App’s User Interface.....................................................249

Chapter 10: Making Applications Fast and Responsive............................................277

Chapter 11: Making Your App Reliable and Secure...................................................293

Part IV: Connecting Your Apps.................................. 327

Chapter 12: Channeling the World Into Your Device ................................................329

Chapter 13: Harnessing iOS Device Capabilities........................................................345

Chapter 14: Publishing to the App Store ....................................................................375

Part V: The Part of Tens ........................................... 399

Chapter 15: Ten Resources for Object-Oriented Development ...............................401

Chapter 16: Ten Developer Resources for iOS...........................................................413

Index ..................................................................... 423

Table of Contents

Introduction ................................................................. 1

About This Book ..............................................................................................1

Foolish Assumptions.......................................................................................3

Icons Used in This Book .................................................................................3

Beyond the Book .............................................................................................4

Part I: Getting Started with iOS Programming ................ 5

Chapter 1: Entering Mobile Application Development . . . . . . . . . . . . . . 7

Apps for a Mobile Platform ............................................................................7

iOS Benefits ....................................................................................................10

iOS App Development Essentials.................................................................12

Devices ..................................................................................................12

Application development technologies ............................................13

Xcode.....................................................................................................18

The Application Model .................................................................................19

Understanding the lifecycle of an iOS app........................................20

Understanding the structure of an iOS app......................................22

Object-Orientation Concepts .......................................................................23

Chapter 2: Object-Oriented Design Principles . . . . . . . . . . . . . . . . . . . 25

Basic Object-Oriented Concepts .................................................................25

Designing programs.............................................................................26

Structural and behavioral concepts in OO.......................................36

Principles of Object-Orientation..................................................................38

Coupling ................................................................................................39

Cohesion ...............................................................................................40

Designing an Object-Oriented Application.................................................40

Advanced OO Techniques............................................................................42

Delayed binding ...................................................................................42

Delegation.............................................................................................43

Design patterns ....................................................................................43

Inversion of control and software frameworks................................44

The Application Development Lifecycle.....................................................45

Software development lifecycle processes ......................................46

The phases and stages of a software development

lifecycle (SDLC) ................................................................................47

The guiding principles of SDLC methodologies...............................50

Customizing an SDLC methodology ..................................................51

vi Beginning iOS Programming For Dummies

Chapter 3: Effectively Using Objective-C . . . . . . . . . . . . . . . . . . . . . . . . 55

Examining an Objective-C Program.............................................................55

Defining Classes.............................................................................................58

Declaring instance variables ..............................................................61

Declaring methods...............................................................................62

Using forward references....................................................................64

Implementing classes ..........................................................................65

Using Classes, Objects, Methods, and Variables.......................................66

Invoking methods ................................................................................66

Creating objects ...................................................................................67

Using all the language features ..........................................................69

Using introspection and dynamic invocation ..................................80

Managing Memory.........................................................................................82

Handling Exceptions .....................................................................................84

Organizing Program Files .............................................................................85

Analyzing Objective-C’s Object-Orientation Capabilities.........................86

Part II: Meeting the Methods and Platforms ................. 89

Chapter 4: Patterns and Frameworks . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

Common Patterns of OO Design..................................................................91

Seeing basic design patterns..............................................................92

Understanding the Model-View-Controller.......................................98

Making model objects persistent.......................................................99

Avoiding anti-patterns.......................................................................105

Applying patterns to application design.........................................106

Understanding Frameworks .......................................................................106

Inversion of control ...........................................................................106

Basic concepts ...................................................................................107

Flow of control ...................................................................................109

Chapter 5: Setting Up to Develop iOS Apps . . . . . . . . . . . . . . . . . . . . . 113

Becoming an iOS Developer .......................................................................113

Installing, Verifying, and Understanding the Xcode

Development Environment.....................................................................119

Installing Xcode..................................................................................119

Verifying the development environment........................................121

Understanding the elements of an Xcode workspace...................127

Importing and Running the Tic-Tac-Toe Sample Program.....................128

Importing Tic-Tac-Toe and running it on the simulator ...............128

Deploying an App on an iOS device.................................................130

Table of Contents vii

Chapter 6: Developing an App on iOS . . . . . . . . . . . . . . . . . . . . . . . . . . 135

Dissecting an iOS App.................................................................................135

Understanding an App’s Lifecycle.............................................................138

Interacting with the App Through Its User Interface..............................141

Dealing with Data.........................................................................................141

Using JSON..........................................................................................142

Saving data using files .......................................................................145

Moving up to Core Data ....................................................................149

Accessing the Address Book ............................................................158

Setting options for your app.............................................................160

Sharing data across apps..................................................................164

Using Other iOS Capabilities on a Device.................................................165

Visiting the App Templates in Xcode........................................................166

Deconstructing the iOS Framework Using OO Principles

and Design Patterns.................................................................................169

Seeing object-oriented concepts and techniques in iOS ..............169

Seeing patterns in iOS .......................................................................170

Critiquing the iOS framework from the perspective of 

OO principles..................................................................................171

Chapter 7: Illustrating Object-Oriented iOS App Design . . . . . . . . . . 173

Customizing an SDLC for iOS App Development.....................................173

Developing Use Cases .................................................................................175

Creating the User Interface ........................................................................177

Illustrating Object-Oriented Design...........................................................180

Classes and responsibilities .............................................................181

Collaborators and missing classes and responsibilities...............183

Contracts and signatures..................................................................186

Implementing an Object-Oriented Design on iOS....................................188

Implementing the model...................................................................188

Creating storyboards and views......................................................193

Making the app active .......................................................................195

Analyzing the OO and Design Principles Used in Tic-Tac-Toe ..............199

Use of design patterns in Tic-Tac-Toe.............................................201

Other concepts...................................................................................204

Part III: Making Your iOS Apps Fit for Consumption.... 207

Chapter 8: Effectively Using Xcode . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209

Xcode and IOS — A Beautiful Friendship .................................................210

Setting up your app’s project...........................................................211

Creating your app’s screen flow ......................................................214

viii Beginning iOS Programming For Dummies

Writing your app’s code....................................................................222

Managing and maintaining your app’s components .....................227

Fine-Tuning Your App in Xcode.................................................................237

Configuring your app.........................................................................237

Digging into the Simulator ................................................................239

Exploring your iOS device from Xcode ...........................................240

Debugging your app ..........................................................................243

Using instruments to collect data....................................................244

Getting Help..................................................................................................247

Chapter 9: Developing Your App’s User Interface . . . . . . . . . . . . . . . . 249

Understanding How User Interfaces Work in iOS....................................249

Comprehending event-driven programming in iOS.......................250

Understanding the Application and the Application

Delegate objects in UI processing................................................250

Revisiting the Model-View-Controller Design Pattern ............................253

Understanding the UI Components Available in iOS...............................256

Interacting with buttons, text fields, and labels ............................258

Alerting the user ................................................................................262

Selecting items using pickers ...........................................................264

Showing columnar data using a Table view ...................................266

Going through the other views in the iOS framework...................268

Navigating through a stack of screens using

a Navigation controller..................................................................269

Drawing using 2-D Graphics .............................................................272

Chapter 10: Making Applications Fast and Responsive . . . . . . . . . . . 277

Becoming Familiar with Nonfunctional Requirements ...........................278

Designing Your App at Multiple Levels.....................................................279

Optimizing an Application’s Performance ...............................................280

Using Instrumentation for Code Optimization.........................................282

Ensuring Responsiveness in Your Apps ...................................................287

Ensuring responsiveness by using threading ................................288

Other Performance Considerations for iOS Apps ...................................291

Chapter 11: Making Your App Reliable and Secure . . . . . . . . . . . . . . 293

Making Your App Reliable Through Testing............................................293

Understanding the fundamentals and levels of testing ................294

Understanding the levels of testing.................................................294

Using automated testing ...................................................................297

Adapting to Changes in the App’s Environment .....................................304

Implementing reliability while navigating your app’s lifecycle......304

Dealing with missing or transient capabilities...............................309

Considering Security in an iOS App ..........................................................310

Recognizing the importance of security.........................................310

Table of Contents ix

Looking at security holistically........................................................312

Understanding the attack surface and developing

a threat model for an app..............................................................314

Implementing authentication and access control .........................316

Protecting core data files with encryption.....................................319

Adding auditing to your application ...............................................323

Part IV: Connecting Your Apps .................................. 327

Chapter 12: Channeling the World Into Your Device . . . . . . . . . . . . . 329

Networking Basics .......................................................................................329

Launching a browser from your app...............................................330

Embedding a browser in your iOS application

using WebView...................................................................................332

Using Maps and Providing Location-Based Services ..............................334

Installing the additional development components needed

for maps...........................................................................................336

Displaying a map using a MapView .................................................337

Using geocoding to navigate the map .............................................338

Wherever you go, there you are ......................................................339

Design Principles for Web- and Location-Based Apps............................343

Being nice about using remote services .........................................343

Using threading to deal with slow network connections .............343

Chapter 13: Harnessing iOS Device Capabilities . . . . . . . . . . . . . . . . 345

Integrating E-Mail, SMS, and the Phone into Your App ..........................346

Sending e-mail from your app ..........................................................346

Sending an SMS from your app ........................................................349

Placing telephone calls from your app ...........................................351

Playing and Capturing Audio, Video, and Images ...................................352

Playing and recording video.............................................................353

Playing and recording audio ............................................................356

Working with images .........................................................................358

Seeing the Capabilities Available on Your Device...................................361

Testing for network availability.......................................................361

Testing for sound and camera capabilities ....................................362

Declaring an app’s needs in the .plist file.......................................364

Bringing in the Outside World with Sensors............................................364

Sensing orientation............................................................................365

Sensing the accelerometer, gyroscope, and magnetometer ........367

Examining OO and Other Design Principles in this Chapter..................370

Seeing uses of loose coupling...........................................................371

Using delegation for customized processing .................................371

Using design patterns........................................................................372

Design tradeoffs in Tic-Tac-Toe .......................................................373

x Beginning iOS Programming For Dummies

Chapter 14: Publishing to the App Store . . . . . . . . . . . . . . . . . . . . . . . . 375

Creating Your Developer Account ............................................................375

Distributing Applications ...........................................................................378

Providing basic application details .................................................378

Special capabilities ............................................................................381

Internationalization and localization...............................................382

Testing ..........................................................................................................383

iOS devices .........................................................................................383

Beta testing.........................................................................................388

Submitting Your App...................................................................................390

Using iTunes Connect........................................................................390

Uploading to the App Store ..............................................................394

Supporting Your App ..................................................................................396

Marketing ............................................................................................396

Sales data and customer feedback ..................................................397

Publishing updates ............................................................................398

Part V: The Part of Tens............................................ 399

Chapter 15: Ten Resources for Object-Oriented Development . . . . . 401

Design Patterns: Elements of Reusable Object-Oriented

Software...........................................................................................401

martinfowler.com...............................................................................402

Object-Oriented Programming with Objective-C...........................403

The Journal of Object Technology ..................................................404

Massively Open Online Courses (MOOCs).....................................405

Ambysoft.............................................................................................406

Craig Larman’s Use Case Primer......................................................407

uml.org ................................................................................................408

Agile Alliance......................................................................................409

Rajiv’s YouTube Video Series ..........................................................410

Chapter 16: Ten Developer Resources for iOS . . . . . . . . . . . . . . . . . . . 413

iOS Dev Center ...................................................................................413

Apple Worldwide Developers Conference......................................414

iOS Dev Weekly ..................................................................................415

raywenderlich ....................................................................................416

AppCoda..............................................................................................417

Stack Overflow ...................................................................................418

iPhoneDevSDK....................................................................................419

Table of Contents xi

pttrns...................................................................................................420

Cocoa Controls...................................................................................420

MacRumors.........................................................................................421

Index....................................................................... 423

xii Beginning iOS Programming For Dummies

Introduction

Although iOS powers only about 13 percent of the smartphones used by

people in the U.S., its use increases to 55 percent when you consider traffic

over the Internet — because iOS devices are bought by people who use their

devices frequently. In addition to its loyal users, iOS comes with a well-designed

Objective-C–based SDK with rich functionality that makes developing apps

straightforward and fun. In other words, iOS is a perfect target market for an

innovative app developer. With that, welcome to this book.

About This Book

This book guides you through the iOS SDK and how to build high-quality appli￾cations using it. It focuses on iOS 7 and Xcode version 5 and is of significant

value to software developers, regardless of their level of experience.

✓ If you’re a software developer and want to understand how to apply

object-oriented concepts, techniques, and principles to iOS develop￾ment, this book is for you.

✓ If you’re a software developer and have developed other kinds applications

but not those for mobile devices, don’t worry. This book is a mobile applica￾tions primer that deals with resource conservation, network disconnection,

change in location, hardware-software interaction, and more.

✓ If you’re a software developer with experience in developing mobile

applications and want to develop an equivalent iOS application (such as

iPhone), you’ll probably quickly understand the iOS programming model

and then navigate on to the chapters you’re most interested in.

Here are some of the conventions you will see in the book:

✓ Code examples: These appear in a fixed-width font so that they stand

out, as illustrated here:

[self initializeGameSession];