Preface
Object-oriented programming, also known as OOP, is a required skill in absolutely any modern software developer job. It makes a lot of sense because object-oriented programming allows you to maximize code reuse and minimize maintenance costs. However, learning object-oriented programming is challenging because it includes too many abstract concepts that require real-life examples to be easy to understand. In addition, object-oriented code that doesn’t follow best practices can easily become a maintenance nightmare.
Swift is a multiparadigm programming language and one of its most important paradigms is OOP. If you want to create great applications and apps for Mac, iPhone, iPad, Apple TV, and Apple Watch (Mac OS, iOS, tvOS, and watchOS operating systems) you need to master OOP in Swift 3. However, Swift 3 is not limited to Apple platforms and you can take advantage of your Swift 3 knowledge to develop applications that target other platforms and use it for server-side code. In addition, as Swift also grabs nice features found in functional programming languages, it is convenient to know how to mix OOP code with functional programming code.
This book will allow you to develop high-quality reusable object-oriented code in Swift 3. You will learn the OOP principles and how Swift implements them. You will learn how to capture objects from real-world elements and create object-oriented code that represents them. You will understand Swift’s approach towards object-oriented code. You will maximize code reuse and reduce maintenance costs. Your code will be easy to understand and it will work with representations of real-life elements.
What this book covers
Chapter 1 , Objects from the Real World to the Playground , covers the principles of object-oriented paradigms. We will understand how real-world objects can become part of fundamental elements in the code. We will translate elements into the different components of the object-oriented paradigm supported in Swift 3--classes, protocols, properties, methods, and instances. We will run examples in Xcode 8, the Swift REPL and a web-based Swift 3 sandbox.
Chapter 2 , Structures, Classes, and Instances, explains generating blueprints to create objects. You will learn about an object’s life cycle and work with many examples to understand how object initializers and deinitializers work.
Chapter 3 ,Encapsulation of Data with Properties , explains organizing data in the blueprints that generate objects. You will understand the different members of a class and how its different members are reflected in members of the instances generated from a class. We will learn the difference between mutable and immutable classes.
Chapter 4 , Inheritance, Abstraction, and Specialization , helps you in creating a hierarchy of blueprints that generate objects. We will take advantage of inheritance and many related features to specialize behavior.
Chapter 5 , Contract Programming with Protocols , delves into how Swift works with protocols in combination with classes. We will declare and combine multiple blueprints to generate a single instance. We will declare protocols with different types of requirements, and then, we will create classes that conform to these protocols.
Chapter 6 , Maximization of Code Reuse with Generic Code , covers how to maximize code reuse by writing code capable of working with objects of different types, that is, instances of classes that conform to specific protocols or whose class hierarchy includes specific superclasses. We will work with protocols and generics.
Chapter 7 , Object-Oriented Programming and Functional Programming , covers how to refactor existing code to take full advantage of object-oriented code. We will prepare the code for future requirements, reduce maintenance cost, and maximize code reuse. We will also work with many functional programming features included in Swift 3, combined with object-oriented programming.
Chapter 8 , Protection and Organization of Code , puts together all the pieces of the object-oriented puzzle. We will take advantage of extensions to add features to types, classes, and protocols to which we don’t have access to the source code. We will make sure that the code exposes only the things that it has to expose, and we will learn how everything we learned about object-oriented programming is useful in any kind of apps we might create.
What you need for this book
In order to work with Xcode 8.x and the Swift Playground, you will need a Mac computer capable of running OS X 10.11.5 or later, with 8 GB RAM.
In order to work with Swift 3.x open source version in the Linux platform, you will need any computer capable of running Ubuntu 14.04 or later, or Ubuntu 15.10 or later. These are the Linux distributions where the Swift open source binaries have been built and tested. It it also possible to run the Swift compiler and utilities on other Linux distributions. You must check the latest available documentation at the Swift open source website: https://swift.org.
In order to work with the web-based IBM Swift Sandbox, you will need any device capable of executing a modern web browser.
Who this book is for
This book is for iOS and Mac OS developers who want to get a detailed practical understanding of object-oriented programming with the latest version of Swift 3.0.
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