Learning Cocoa with Objective-C: Developing for the Mac and iOS App Stores

421 Pages·2012·5.9 MB·English

by  Paris Buttfield-Addison

Learning Cocoa with Objective-C
Paris Buttfield-Addison
Jonathon Manning
Published by O’Reilly Media
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Preface
We’ve been developing for the Cocoa framework from when the Mac first
supported it. Since then, we’ve seen the ecosystem of Cocoa and Objective-C
development evolve from a small programmer’s niche to one of the most important
and influential development environments in the world. (In fact, as 2012 closes,
Objective-C is the third most popular programming language according to the
TIOBE index, up from fifth most popular in 2011.)
Over the years, we’ve built a lot of large, complex iOS and OS X software,
shipping it to millions upon millions of users along the way. We’ve picked up a
deep understanding of the toolset, frameworks, and programming language, an
understanding crucial to building the best possible software for iOS and OS X.
Apple constantly changes things, as the recent introduction of the svelte iPad mini
and the stretched iPhone 5 show, but the knowledge necessary to bend the
development tools, frameworks and languages to your will stays fairly constant.
This book will give you the knowledge, confidence, and appreciation for iOS and
OS X development with Cocoa, Cocoa Touch, and Objective-C.
Audience
We assume that you’re a reasonably capable programmer, but we don’t assume
you’ve ever developed for iOS or OS X, or used Objective-C before. We also
assume that you’re fairly comfortable navigating OS X as a user, and know how to
use an iOS device.
Organization of This Book
In this book, we’ll be talking about Cocoa and Cocoa Touch, the frameworks used
on OS X and iOS, respectively. Along the way, we’ll also be covering Objective-C,
including its syntax and features. Pretty much every chapter contains practical
exercises that you can follow along with. The early chapters cover general topics,
such as setting up a development environment and coming to grips with the
Objective-C language, while later chapters cover specific features of Cocoa and
Cocoa Touch.
Here is a concise breakdown of the material each chapter covers:
Chapter 1, Cocoa Development Tools
This chapter introduces Cocoa and Cocoa touch, the frameworks used on OS
X and iOS. Introduces Xcode, the IDE that you’ll be using while coding for
these platforms. This chapter also covers the Apple Developer Programs, which
are necessary if you want to distribute software on the Mac or iTunes App
Stores.
Chapter 2, Object-Oriented Programming with Objective-C
This chapter covers object-oriented programming, the programming paradigm
used in Objective-C, as well as how Objective-C implements object-oriented
programming. This chapter also covers memory management in Cocoa and
Cocoa touch, which is one of the most important things to understand when
developing for the Mac and for iOS.
Chapter 3, Foundation
This chapter introduces the Foundation framework, which provides the basic
data types (like strings, arrays, and dictionaries). This chapter also discusses the
underlying design patterns on which much of Cocoa and Cocoa Touch are
based.
Chapter 4, Applications on OS X and iOS
This chapter discusses how applications are assembled and operate on Mac and
iOS devices. In this chapter, we’ll talk about the application lifecycle on both
platforms, as well as how sandboxing affects application access to data and
resources.
Chapter 5, Graphical User Interfaces
This chapter demonstrates how user interfaces are loaded and presented to the
user. This chapter introduces one of the most powerful concepts provided by
Cocoa: nibs, which are predesigned and preconfigured user interfaces, and
which can be directly connected to your code. This chapter also discusses Core
Animation, the animation system used on OS X and iOS.
Chapter 6, Blocks and Operation Quotes
This chapter introduces blocks, which are an incredibly flexible and useful
addition that Objective-C introduces to the C language. Blocks are functions
that can be stored in variables and passed around like values. This makes things
like callbacks very simple to implement. This chapter also introduces operation
queues, which are a straightforward way to work with concurrency without
having to deal with threads.
Chapter 7, Drawing Graphics in Views
In this chapter, you’ll learn about the drawing system used on both OS X and
iOS, as well as how to draw custom graphics. The retina display is also
covered, as well as how view geometry works.
Chapter 8, Audio and Video
This chapter covers audio and video playback using AVFoundation, the audio
and video engine. You’ll also learn how to access the iOS photo library and get
access to the user’s photos.
Chapter 9, Model Objects and Data Storage
This chapter covers a range of data storage options available on OS X and iOS.
Key-Value Coding and Key-Value Observing, preferences, notifications, and
filesystem access are all covered. In addition, you’ll learn how to make
security-scoped bookmarks, which allow sandboxed apps to retain access to
locations that the user has granted your apps permission to use.
Chapter 10, Cocoa Bindings
This chapter covers Cocoa Bindings, a tremendously powerful system that
allows you to connect your application’s user interface to an application’s data,
without the need for intermediary “glue code.”
Chapter 11, Table Views and Collection Views
This chapter covers table views (an effective way to display multiple rows of
data to your user) and collection views, which allow you to display a collection
of items to the user.
Chapter 12, Document-Based Applications
This chapter discusses the document systems on both iOS and OS X, which are
instrumental in creating applications that work with multiple documents. Here,
we discuss the differences in how the two platforms handle documents.
Chapter 13, Networking
Cocoa and Cocoa Touch provide very straightforward tools for accessing
networked resources, and this chapter demonstrates how to retrieve
information from the internet while keeping the application responsive. This
chapter also covers the network service discovery system, Bonjour.
Chapter 14, Working with the Real World
This chapter covers a variety of technologies used to work with the physical
world: Core Location, for getting access to the GPS; Core Motion, for learning
about how the hardware is moving and oriented, and the printing systems on
both iOS and OS X.
Chapter 15, Event Kit
This chapter discusses the calendaring system used on iOS and OS X, and
demonstrates how to get access to the user’s calendar. We also discuss
considerations for user privacy.
Chapter 16, Instruments and the Debugger
This chapter covers Instruments, the profiler and analysis tool for Mac and iOS
applications. An example of a crashing application is discussed, and the cause
of the crash is diagnosed and fixed using the application. Additionally, this
chapter covers Xcode’s built-in debugger.
Chapter 17, Sharing and Notifications
This chapter discusses how applications can share text, images, and other
content with various other services like Twitter and Facebook, using the built-
in sharing systems (which don’t require your application to deal with
authenticating to these services). Additionally, we’ll cover both push
notifications and local notifications, which allow your application to display
information to the user without running.
Chapter 18, Nonstandard Apps
Not every program you write will be an app that sits on the user’s home screen,
and this chapter tells you how to write three different kinds of non-traditional
apps: command-line tools, menu bar apps, and preference panes.
Chapter 19, Working with Text
This chapter covers the string localization system available on iOS and OS X.
Here, we discuss data extraction from text using the built-in Data Detectors.
Chapter 20, iCloud
This chapter discusses iCloud, the cloud data storage and syncing system
provided by Apple. The functionality and requirements of iCloud are discussed,
as well as demonstration apps for both OS X and iOS.
Conventions Used in This Book
The following typographical conventions are used in this book:
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Constant width
Used for program listings, as well as within paragraphs to refer to program
elements such as variable or function names, databases, data types,
environment variables, statements, and keywords.
Constant width bold
Shows commands or other text that should be typed literally by the user.
Constant width italic
Shows text that should be replaced with user-supplied values or by values
determined by context.
TIP
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CAUTION
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Using Code Examples
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Jonathon Manning and Paris Buttfield-Addison, 978-1-449-31849-9.”
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