Swift 2 Design Patterns

Julien Lange

• Éditeur: Packt Publishing
• Année: 2015
• ISBN:
  9781785887611
• Édition: 1
• Sujet: Computer Science
• Sous-sujet: Application Development

Build robust and scalable iOS and Mac OS X game applications

About This Book

• Learn to use and implement the 23 Gang of Four design patterns using Swift 2
• Design and architect your code for Swift application development
• Understand the role, generic UML design, and participants in the class diagram of the pattern by implementing them in a step-by-step approach

Who This Book Is For

This book is intended for competent Swift developers who want to apply enduring design patterns with Swift to structure and scale their application code.

What You Will Learn

• Choose the appropriate pattern depending on the problem to be solved
• Understand the generic class diagram of each of the 23 GoF patterns and how each object participates in the pattern
• Use Swift to implement these patterns even though the language doesn't provide all of the object-oriented programming concepts such as abstract class, interface, and so on
• Architect your software to avoid the overuse of memory, time spent on calculations, or high network traffic
• Find the best way to organize your code to make it more secure from the outside world
• Prepare your code to make it more flexible when the consumer changes or the third-party component hidden code changes
• Structure your code to change the algorithm to apply at runtime
• Deliver Flyweight responsibility to your objects

In Detail

Swift is a multi-paradigm language. It has expressive features familiar to those used to work with modern functional languages, while also keeping the object-oriented features of Objective-C. It remains compatible with Apple's legacy codes and frameworks. A design pattern systematically names, motivates, and explains a general design that addresses a recurring design problem in object-oriented systems. It describes the problem, the solution, when to apply the solution, and its consequences. It also gives implementation hints and examples. Knowledge about design patterns is also one of the best ways to make you different compared to other low-level developers.

This book shows you how to use Swift 2 to learn about 23 Gang of Four (GoF) design patterns, and is organized into three categories. The book will present you the five creational patterns, followed by the seven structural patterns, and finishing with the 11 behavioral patterns as defined by the GoF. Each chapter will introduce the pattern by defining its role, which common problems the pattern should be used for, its generic UML representation, how each objects presented in the class diagram participate in the pattern, and what the role of each of these objects is. The book then presents you with a concrete case as an illustration that will be used to implement the pattern using Swift.

Style and approach

A step-by-step tutorial completed with screenshots and code highlights wherever necessary. Each chapter discusses one or more patterns with its definitions and a simple-to-follow illustration case using a playground or XCText project to implement it with Swift.

Swift 2 Design Patterns

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Table of Contents

Swift 2 Design Patterns

Credits

About the Author

About the Reviewers

www.PacktPub.com

Support files, eBooks, discount offers, and more

Why subscribe?

Free access for Packt account holders

Preface

What this book covers

What you need for this book

Who this book is for

Conventions

Reader feedback

Customer support

Downloading the example code

Downloading the color images of this book

Errata

Piracy

eBooks, discount offers, and more

Questions

1. Creational Patterns

The prototype pattern

Roles

Design

Participants

Collaborations

Illustration

Implementation

Usage

The factory method pattern

Roles

Design

Participants

Illustration

Implementation

Usage

The singleton pattern

Roles

Design

Participants

Collaborations

Illustration

Implementation

Usage

The abstract factory pattern

Roles

Design

Participants

Collaborations

Illustration

Implementation

Usage

The builder pattern

Roles

Design

Participants

Collaborations

Illustration

Implementation

Usage

Implementation using closures

Summary

2. Structural Patterns – Decorator, Proxy, and Bridge

Static and dynamic composition

The decorator pattern

Roles

Design

Participants

Collaboration

Sample

Implementation

Usage

The proxy pattern

Roles

Design

Participants

Collaboration

Illustration

Implementation

Usage

The bridge pattern

Roles

Design

Participants

Collaboration

Illustration

Implementation

Usage

Summary

3. Structural Patterns – Composite and Flyweight

The composite pattern

Roles

Design

Participants

Collaboration

Illustration

Implementation

Implementation of the VODComponent

Implementation of the VODItem leaf

Implementation of the VODCategory composite

Usage

The flyweight pattern

Roles

Design

Participants

Collaboration

Illustration

Implementation

Usage

Performance results

Summary

4. Structural Patterns – Adapter and Facade

The adapter pattern

Roles

Design

Participants

Collaboration

Illustration

Implementing our first prototype

Implementation

Implementation of our adaptees

Implementation of the SamSingAdapter class

Implementation of the PearAdapter class

The facade pattern

Roles

Design

Participants

Collaboration

Illustration

Implementation of the facade

Summary

5. Behavioral Patterns – Strategy, State, and Template Method

The strategy pattern

Roles

Design

Participants

Collaboration

Illustration

Implementation

The state pattern

Role

Design

Participants

Collaboration

Illustration

Implementation

The template method

Role

Design

Participants

Collaboration

Illustration

Implementation

Summary

6. Behavioral Patterns – Chain of Responsibility and Command

The chain of responsibility pattern

Roles

Design

Participants

Collaboration

Illustration

Implementation

The command pattern

Roles

Design

Participants

Collaboration

Illustration

Implementation

Comparison between the chain of responsibility and command patterns

Summary

7. Behavioral Patterns – Iterator, Mediator, and Observer

The iterator pattern

Roles

Design

Participants

Collaboration

Illustration

Implementation

The mediator pattern

Roles

Design

Participants

Collaboration

Illustration

Implementation

The observer pattern

Roles

Design

Participants

Collaboration

Illustration

Implementation

Summary

8. Behavioral Patterns – Visitor, Interpreter, and Memento

The visitor pattern

Roles

Design

Participants

Collaboration

Illustration

Implementation

The interpreter pattern

Roles

Design

Participants

Collaboration

Illustration

Implementation

The memento pattern

Roles

Design

Participants

Collaboration

Illustration

Implementation

Comparing the three patterns

Summary

Index

Swift 2 Design Patterns

Copyright © 2015 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews.

Every effort has been made in the preparation of this book to ensure the accuracy of the information presented. However, the information contained in this book is sold without warranty, either express or implied. Neither the author, nor Packt Publishing, and its dealers and distributors will be held liable for any damages caused or alleged to be caused directly or indirectly by this book.

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First published: October 2015

Production reference: 1231015

Published by Packt Publishing Ltd.

Livery Place

35 Livery Street

Birmingham B3 2PB, UK.

ISBN 978-1-78588-761-1

www.packtpub.com

Credits

Author

Julien Lange

Reviewers

Vladimir Pouzanov

Victor Sigler

Ye Xiaodong

Acquisition Editor

Tushar Gupta

Content Development Editor

Shali Deeraj

Technical Editor

Saurabh Malhotra

Copy Editors

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Sneha Singh

Project Coordinator

Kinjal Bari

Proofreader

Safis Editing

Indexer

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Graphics

Disha Haria

Jason Monteiro

Abhinash Sahu

Production Coordinator

Komal Ramchandani

Cover Work

Komal Ramchandani

About the Author

Julien Lange is a 34-year-old IT expe...