ActionScript 3.0 Design Patterns
William B. Sanders and
Chandima Cumaranatunge
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ActionScript 3.0 Design Patterns
by William B. Sanders and Chandima Cumaranatunge
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vii
Table of Contents
Preface
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
xi
Part I. Constant Change
1. Object-Oriented Programming, Design Patterns, and ActionScript 3.0
. . . . .
3
The Pleasure of Doing Something Well 3
OOP Basics 10
Abstraction 11
Encapsulation 15
Inheritance 24
Polymorphism 34
Principles of Design Pattern Development 42
Program to Interfaces over Implementations 45
Favor Composition 49
Maintenance and Extensibility Planning 57
Your Application Plan: It Ain’t You Babe 60
Part II. Creational Patterns
2. Factory Method Pattern
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
65
What Is the Factory Method Pattern? 65
Abstract Classes in ActionScript 3.0 68
Minimalist Example 69
Hiding the Product Classes 73
Example: Print Shop 74
Extended Example: Color Printing 80
Key OOP Concepts Used in the Factory Method Pattern 84
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