Ruby on Rails for all. - Chapter 6. Ajax

Contents

Ruby on Rails: Up and Running

Table of Contents

Chapter 1. Zero to Sixty: Introducing Rails

Section 1.1. Rails Strengths

Section 1.2. Putting Rails into Action

Section 1.3. Organization

Section 1.4. The Web Server

Section 1.5. Creating a Controller

Section 1.6. Building a View

Section 1.7. Tying the Controller to the View

Section 1.8. Under the Hood

Section 1.9. What's Next?

Chapter 2. Active Record Basics

Section 2.1. Active Record Basics

Section 2.2. Introducing Photo Share

Section 2.3. Schema Migrations

Section 2.4. Basic Active Record Classes

Section 2.5. Attributes

Section 2.6. Complex Classes

Section 2.7. Behavior

Section 2.8. Moving Forward

Chapter 3. Active Record Relationships

Section 3.1. belongs_to

Section 3.2. has_many

Section 3.3. has_one

Section 3.4. What You Haven't Seen

Section 3.5. Looking Ahead

Chapter 4. Scaffolding

Section 4.1. Using the Scaffold Method

Section 4.2. Replacing Scaffolding

Section 4.3. Generating Scaffolding Code

Section 4.4. Moving Forward

Chapter 5. Extending Views

Section 5.1. The Big Picture

Section 5.2. Seeing Real Photos

Section 5.3. View Templates

Section 5.4. Setting the Default Root

Section 5.5. Stylesheets

Section 5.6. Hierarchical Categories

Section 5.7. Styling the Slideshows

Chapter 6. Ajax

Section 6.1. How Rails Implements Ajax

Section 6.2. Playing a Slideshow

Section 6.3. Using Drag-and-Drop to Reorder Slides

Section 6.4. Drag and Drop Everything (Almost Everything)

Section 6.5. Filtering by Category

Chapter 7. Testing

Section 7.1. Background

Section 7.2. Ruby's Test::Unit

Section 7.3. Testing in Rails

Section 7.4. Wrapping Up

Appendix A. Installing Rails

Section 1.1. Windows

Section 2.1. OS X

Section 3.1. Linux

Appendix B. Quick Reference

Section 5.1. General

Section 5.2. Testing

Section 5.3. RJS (Ruby JavaScript)

Section 5.4. Active Record

Section 5.5. Controllers

Section 5.6. Views

Section 5.7. Ajax

Section 5.8. Configuring Your Application

About the Authors

Index

A

B

C

D

E

F

G

H

I

J

L

M

N

O

P

R

S

T

U

V

W

X

Y

Z

Ruby on Rails for all.

Chapter 6. Ajax

Ajax is one of the most important emerging trends in web applications. Web sites like Google Maps and Gmail dramatically demonstrate that web applications do not have to be slow, clunky, page-at-a-time web forms. Ajax techniques can reclaim some of the fluidity and responsiveness that was lost when we moved from desktop applications to web applications.

Ajax (which stands for the cryptic "Asynchronous JavaScript and XML") is a technique for building web pages that are more interactive, exciting, and dynamic. Ajax is asynchronous: JavaScript libraries can communicate with the server at any time, and the web page need not be frozen while waiting for a response. Ajax uses JavaScript on the browser, any language on the server, and XML to specify messages.

When you use this emerging technique, a web page can communicate with the server at any time, updating only those portions of the display that need it. Users experience more responsive web pages, with immediate feedback. Even though using Ajax techniques usually requires significantly more sophisticated design and implementation skills, the benefits to the end user are so great that Ajax-enabled web applications will soon become the rule, not the exception. Fortunately, Rails makes Ajax so simple that, for typical cases, using Ajax is almost as easy as not using it.