ActionScript 3.0 Design Patterns

دوره آموزش Javascript 

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

Example: Sprite Factory 84

Example: Vertical Shooter Game 90

Summary 100

3. Singleton Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

What Is the Singleton Pattern? 101

Key OOP Concepts Used with the Singleton Pattern 102

Minimalist Abstract Singleton 105

When to Use the Singleton Pattern 112

Summary 125

Part III. Structural Patterns

4. Decorator Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

What Is the Decorator Pattern? 129

Key OOP Concepts Used with the Decorator Pattern 132

Minimalist Abstract Decorator 135

Applying a Simple Decorator Pattern in Flash: Paper Doll 141

Decorating with Deadly Sins and Heavenly Virtues 148

Dynamic Selection of Concrete Components and Decorations:

A Hybrid Car Dealership 164

Summary 176

5. Adapter Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177

What Is the Adapter Pattern? 177

Object and Class Adapters 179

Key OOP Concepts in the Adapter Pattern 185

Example: Car Steering Adapter 185

Extended Example: Steering the Car Using a Mouse 193

Example: List Display Adapter 194

Extended Example: Displaying the O’Reilly New Books List 199

Summary 203

6. Composite Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204

What Is the Composite Pattern? 204

Minimalist Example of a Composite Pattern 207

Key OOP Concepts in the Composite Pattern 217

Example: Music Playlists 217

Example: Animating Composite Objects Using Inverse Kinematics 22

Using Flash’s Built-in Composite Structure: the Display List 233

Summary 243

Part IV. Behavioral Patterns

7. Command Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247

What Is the Command Pattern? 247

Minimalist Example of a Command Pattern 251

Key OOP Concepts in the Command Pattern 255

Minimalist Example: Macro Commands 255

Example: Number Manipulator 258

Extended Example: Sharing Command Objects 263

Extended Example: Implementing Undo 266

Example: Podcast Radio 270

Extended Example: Dynamic Command Object Assignment 276

Summary 281

8. Observer Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282

What Is the Observer Pattern? 282

Key OOP Concepts Used with the Observer Pattern 285

Minimalist Abstract Observer 289

Example: Adding States and Identifying Users 294

Dynamically Changing States 302

Example: Working with Different Data Displays 318

Summary 330

9. Template Method Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331

What Is the Template Method Pattern? 331

Key OOP Concepts Used with the Template Method 335

Minimalist Example: Abstract Template Method 338

Employing Flexibility in the Template Method 341

Selecting and Playing Sound and Video 344

Hooking It Up 351

Summary 356

10. State Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 357

Design Pattern to Create a State Machine 357

Key OOP Concepts Used with the State Pattern 360

Minimalist Abstract State Pattern 361

Video Player Concrete State Application 367

Expanding the State Design: Adding States 374

Adding More States and Streaming Capabilities 382

Summary 397

11. Strategy Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398

What Is the Strategy Pattern? 398

Key OOP Concepts Used with the Strategy Pattern 400

Minimalist Abstract State Pattern 402

Adding More Concrete Strategies and Concrete Contexts 406

Working with String Strategies 414

Summary 423

Part V. Multiple Patterns

12. Model-View-Controller Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 427

What Is the Model-View-Controller (MVC) Pattern? 427

Communication Between the MVC Elements 428

Embedded Patterns in the MVC 430

Minimalist Example of an MVC Pattern 431

Key OOP Concepts in the MVC Pattern 443

Example: Weather Maps 443

Extended Example: Infrared Weather Maps 451

Example: Cars 457

Custom Views 463

Adding a Chase Car 466

Summary 468

13. Symmetric Proxy Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 469

Simultaneous Game Moves and Outcomes 469

The Symmetric Proxy Pattern 473

Key OOP Concepts Used with the Symmetric Proxy 475

The Player Interface 477

The Referee 478

Information Shared Over the Internet 483

Player-Proxy Classes 486

Classes and Document Files Support 494

Summary 498

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499