ajax! ajax programming ajax! ajax programming. ajax! ajax programming take a look at a typical...

Click here to load reader

Post on 20-Jan-2018

258 views

Category:

Documents

0 download

Embed Size (px)

DESCRIPTION

Ajax! Ajax Programming “Click, wait, and refresh” user interaction Synchronous “request/response” communication model Page-driven: Workflow is based on pages Conventional Web Apps

TRANSCRIPT

Ajax!Ajax Programming
Take a look at a typical desktop application (Spreadsheet app, etc.)
The program responses intuitively and quickly
The program gives a user meaningful feedback's instantly
Things happen naturally
Take A Scenario
Synchronous “request/response” communication model
Conventional Web Apps
Constrained by HTML
These are the reasons why Rich Internet Application (RIA) technologies were born.
Conventional Web Apps Issues
Custom data streaming, graphic manipulation, threading, and GUIs
• Cons:
browser
Applet
Ajax!
• Pros:
• Cons:
ActionScript is proprietary
Disconnected operation is possible
Incremental redeployment
Java Webstart
First-time download time could be still significant
Java Webstart
Not a stand-alone language or technology.
It is a technique that combines a set of known technologies in order to create faster and more user friendly web pages.
It is a client side technology.
AJAX
Ajax!
Flash typically has slower page load time
Flash can work on older browsers
AJAX vs Flash
• ActionScript doesn't have a cross browser issues
• Flash can access other domains if there is a crossdomain.xml file
AJAX vs Flash
Tremendous industry momentum
No need to download code & no plug-in required
Cons
AJAX
Ajax!
Prevents unnecessary reloading of a page.
When we submit a form, although most of the page remains the same, whole page is reloaded from the server.
AJAX Purpose
This causes very long waiting times and waste of bandwidth.
AJAX aims at loading only the necessary innformation, and making only the necessary changes on the current page without reloading the whole page.
AJAX Purpose
No clicking required
Mouse movement is a sufficient event trigger
"Partial screen update" replaces the "click, wait, and refresh" user interaction model
Only user interface elements that contain new information are updated (fast response)
Why AJAX?
Data-driven (as opposed to page-driven)
UI is handled in the client while the server provides data
Asynchronous communication replaces "synchronous request/response model."
A user can continue to use the application while the client program requests information from the server
Why AJAX?
Save Bandwidth
Faster interfaces (sometimes)
Real Life AJAX Example
Ajax Programming
In a creative role playing, think of REAL LIFE good scenarios that will show the concepts of AJAX such:
the interaction of different components
comparison to classic web
Group Activity: