Learning Flex 4: Getting Up to Speed with Rich Internet Application Design and Development (Adobe Dev Lib)

478 Pages·2010·6.913 MB·English

by  Alaric Cole, Elijah Robison

Learning Flex 4
Getting Up to Speed with Rich Internet Application Design and Development
Alaric Cole and Elijah Robison
Beijing • Cambridge • Farnham • Köln • Sebastopol • Tokyo
Learning Flex 4
by Alaric Cole and Elijah Robison
Copyright © 2011 Alaric Cole and Elijah Robison. All rights reserved.
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November 2010: First edition.

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Contents
Preface .... .......... ... .. .. . .. . .. ... ... ... ... .. ... ... .. .. xi
Chapter 1
Getting Up to Speed ... ..... ......... ... ... .. .. ... ... ... 1
What Is Flex? ................................................................. 1
What About AIR? ............................................................. 4
Where Flex Fits ............................................................... 5
Why Use Flex? ................................................................ 6
How Flex Compares to Other Technologies ................................. 8
When Not to Use Flex .......................................................11
Summary ...................................................................11
Chapter 2
Setting Up Your Environment ... .. ............ .. ... .. 13
Using Alternatives to Flash Builder ..........................................14
Introducing Flash Builder and Eclipse .......................................16
Running Your First Application ..............................................20
Creating a New Flex Project .................................................27
Summary ...................................................................29
Chapter 3
Using Design Mode ... ..... ......... ... ... .. .. ... ... .. 31
A Blank Slate: Your First Project ..............................................31
Adding Components to the Application ...................................36
Exploring Common Components ..........................................39
Modifying Properties Directly ...............................................44
Summary ...................................................................50
v
Chapter 4
Using Source Mode .... ............. ... ... .. .. ... ... ... 51
What Design Mode Does ...................................................51
Anatomy of a Flex Application ..............................................52
Adding Components in Source Mode ......................................54
Code Completion ...........................................................55
MXML in Depth .............................................................56
S, FX, and MX: Namespaces Explained ......................................60
Summary ...................................................................62
Chapter 5
ActionScript Basics for Flex Applications ..... ...... 63
Getting Ready ...............................................................63
Dot Notation ................................................................64
Inline ActionScript ..........................................................65
Assignment and Concatenation ............................................66
Functions ...................................................................66
Variables ....................................................................74
Data Types ..................................................................75
Objects ......................................................................78
Classes ......................................................................79
ActionScript’s Relationship with MXML .....................................85
Comments? .................................................................87
Summary ...................................................................88
Chapter 6
Debugging Flex Applications ..... ............ .. ... .. 89
Outputting Values to the Console Using trace() ............................90
Inspecting Event Properties with trace() ....................................93
Using Breakpoints ..........................................................95
Summary ................................................................. 101
Chapter 7
Adding Interaction with ActionScript .... ......... 103
Understanding Events .................................................... 104
Common Events .......................................................... 104
Researching Events ....................................................... 105
Listening for and Responding to Events .................................. 109
Collision! A Whirlwind of Events .......................................... 120
Summary ................................................................. 136
vi Contents
Chapter 8
Using Data Binding ... ..... ......... ... ... .. .. ... ... .. 137
What Is Data Binding? .................................................... 137
Applying Data Binding .................................................... 138
Two-Way Bindings ........................................................ 146
Handling Complex Data with Data Models ............................... 147
When Data Binding Isn’t Appropriate ..................................... 150
Summary ................................................................. 150
Chapter 9
Designing Application Layouts .... ............. ... . 151
Types of Layouts .......................................................... 152
The Display List ........................................................... 155
Sizing ..................................................................... 160
Controlling Whitespace in the Layout .................................... 162
Advanced Containers ..................................................... 165
Spacers and Lines ......................................................... 168
Alignment ................................................................ 171
Constraints-Based Layout ................................................. 173
Summary ................................................................. 176
Chapter 10
Creating Rich Forms ... ..... ......... ... ... .. .. ... ... . 177
Preparing a Form-Based Application ..................................... 177
Validating Data ............................................................ 184
Restricting Input .......................................................... 196
Formatting Input ......................................................... 197
Combining Restrictions and Formatters .................................. 199
Linking Formatters to Functions .......................................... 200
Summary ................................................................. 207
Chapter 11
Gathering and Displaying Data .... ............. ... . 209
Using List-Based Controls ................................................. 209
Using XML Data ........................................................... 217
Implementing List Selection .............................................. 229
Connecting to Search Results............................................. 231
Dragging and Dropping in Lists .......................................... 234
Creating Custom Item Renderers ......................................... 236
Working with External Data Services ..................................... 240
Summary ................................................................. 241
Contents vii
Chapter 12
Controlling Visibility and Navigation ..... ......... 243
Controlling Visibility ....................................................... 244
Navigation Components .................................................. 244
Creating a Photo Gallery Application ..................................... 256
Summary ................................................................. 268
Chapter 13
Working with View States .... ............. ... ... .. .. 269
Scenarios for States ....................................................... 269
Managing States in Design Mode ........................................ 271
Making a Login/Registration Form ........................................ 275
Applying States to the Search Application ............................... 279
Summary ................................................................. 284
Chapter 14
Applying Effects, Transitions, and Filters ..... ..... 285
Effects ..................................................................... 286
Transitions ................................................................ 297
Filters ...................................................................... 306
Summary ................................................................. 312
Chapter 15
Styling and Skinning .... ............. ... ... .. .. ... ... 313
Inline Style Assignments .................................................. 314
Style Blocks and CSS ...................................................... 316
External CSS ............................................................... 320
Skinning .................................................................. 326
Summary ................................................................. 343
Chapter 16
Making Data Dynamic: Linking Flex to the Server ... 345
Some Background Information ........................................... 345
The ContactManager Application ........................................ 347
Linking ContactManager to the Server Using the HTTPService Class .... 356
Summary ................................................................. 364
viii Contents