AJAX_Python-Mines

2010-02-26T06:29:00.001-08:00

test

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Python Set Types:

A set type is a collection data type that supports the membership operator (in), the size function (len()), and is iterable. In addition, set types at least provide a set.isdisjoint() method, and support for comparisons, as well as support for the bitwise operators (which in the context of sets are used for union, intersection, etc.).

Python provides two built-in set types: the mutable set type and the immutable frozenset.

When iterated, set types provide their items in an arbitrary order.

2009-12-18T22:50:00.000-08:00

Simple example python script:

name = raw_input(" What is your pet name? ")

print "Hello, " + name + "!"

If you run this (remember to save it first), you should see the following prompt

in the inter-preter window: What is your pet name?

Enter your pet name (for example, Bunny) and press Enter.

You should get something like this:

What is your pet name? // You enter your pet name: Bunny //

Hello, Bunny!

2009-11-25T22:34:00.000-08:00

Python Collection Data Types:

A sequence type is one that supports the membership operator (in), the size function (len()), slices ([]), and is iterable.
Python provides five built-in sequence types: bytearray, bytes, list, str, and tuple.
Some other sequence types are provided in the standard library, most notably, collections.namedtuple.

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test3

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test2

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Test

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Test

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Python Width and Precision:

A conversion specifier may include a field width and a precision.

The width is the minimum number of characters reserved for a formatted value. The precision is (for a numeric conver-sion) the number of decimals that will be included in the result or (for a string conversion) the maximum number of characters the formatted value may have.

These two parameters are supplied as two integer numbers (width first, then precision),

separated by a . (dot). Both are optional, but if you want to supply only the precision,

you must also include the dot:

>>> '%10f' % pi # Field width 10

' 3.141593'

>>> '%10.2f' % pi # Field width 10, precision 2

' 3.14'

>>> '%.2f' % pi # Precision 2

'3.14'

>>> '%.5s' % 'Guido van Rossum'

'Guido'

You can use an * (asterisk) as the width or precision (or both).

In that case, the number will be read from the tuple argument:

>>> '%.*s' % (5, 'Guido van Rossum')

'Guido'

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Python Simple Conversion:

The simple conversion, with only a conversion type, is really easy to use:

>>> 'Using str: %s' % 99L

'Using str: 99'

>>> 'Using repr: %r' % 99L

'Using repr: 99L'

>>> 'Price of eggs: $%d' % 42

'Price of eggs: $42'

>>> 'Hexadecimal price of eggs: %x' % 42

'Hexadecimal price of eggs: 2a'

>>> from math import pi

>>> 'Pi: %f...' % pi

'Pi: 3.141593...'

>>> 'Very inexact estimate of pi: %i' % pi

'Very inexact estimate of pi: 3'

2009-06-30T08:16:00.000-07:00

Python String Formatting Conversion Types :

Conversion Type Meaning

d, i Signed integer decimal

o Unsigned octal

u Unsigned decimal

x Unsigned hexadecimal (lowercase)

X Unsigned hexadecimal (uppercase)

e Floating-point exponential format (lowercase)

E Floating-point exponential format (uppercase)

f, F Floating-point decimal format

g Same as e if exponent is greater than –4 or less than precision

G Same as E if exponent is greater than –4 or less than precision;

c Single character (accepts an integer or a single character string)

r String (converts any Python object using repr)

s String (converts any Python object using str)

2009-05-25T23:47:00.000-07:00

Concatenating Strings :

>> "Let's say " '"Hello, world!"'

Simply written two strings, one after the other, and Python automatically concate-nates them (makes them into one string).

This mechanism isn’t used very often, but it can be useful at times.

However, it works only when you actually write both strings at the same time, directly following one another:

>>> x = "Hello, "

>>> y = "world!"

>>> x y

SyntaxError: invalid syntax

It is just a special way of writing strings, not a general method of concat-enating them.

How, then, do you concatenate strings? Just like you add numbers:

>>> "Hello, " + "world!"

'Hello, world!'

>>> x = "Hello, "

>>> y = "world!"

>>> x + y

'Hello, world!'

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Single-Quoted Strings and Escaping Quotes :

Strings are values, just as numbers are:

>>> "Hello, world!"

'Hello, world!'

There is one thing that may be a bit surprising about this example, though:

When Python printed out our string, it used single quotes, whereas we used double quotes.

What’s the difference? Actually, there is no difference:

>>> 'Hello, world!'

'Hello, world!'

Here, we use single quotes, and the result is the same. So why allow both?

Because in some cases it may be useful:

>>> "Let's go!"

"Let's go!"

>>> '"Hello, world!" she said'

'"Hello, world!" she said'

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Python Strings :

The raw_input and "Hello, " + name + "!"

Let’s go for the "Hello" part first and leave raw_input for later.

The first program in this chapter was simply print "Hello, world!"

But what is "Hello, world!"? It’s called a string (as in “a string of characters”).

Strings are found in almost every useful, real-world Python program and have many uses.

Their main use is to represent bits of text, such as the exclamation “Hello, world!”

2009-04-22T20:57:00.000-07:00

Running Python Scripts from a Command Prompt :

Actually, there are several ways to run your programs. First, let’s assume that you have a DOS
window or a UNIX shell prompt before you, and that the directory containing the Python exe-
cutable (called python.exe in Windows, and python in UNIX) or the directory containing the
executable (in Windows) has been put in your PATH environment variable.

Also, let’s assume that your script from the previous section (hello.py) is in the current directory. Then you can execute your script with the following command in

Windows: C:\>python hello.py

UNIX: $ python hello.py

As you can see, the command is the same. Only the system prompt changes.

Note : If you don’t want to mess with environment variables, you can simply specify the full path of the Python interpreter.

In Windows, you might do something like this: C:\>C:\Python25\python hello.py

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Saving and Executing Your Programs :

First of all, you need a text editor, preferably one intended for programming. (If you use
something like Microsoft Word, which I don’t really recommend, be sure to save your code as
plain text.)

With IDLE, you can simply create a new editor window with File >> New Window.

Another window appears, without an interactive prompt.

Whew! Start by entering the following:

print "Hello, world!"

Now select File >> Save to save your program (which is, in fact, a plain text file).

Be sure to put it somewhere where you can find it later. You might want to create a directory where you put all your Python projects, such as C:\python in Windows.

In a UNIX environment, you might use a directory like ~/python. Give your file any reasonable name, such as hello.py. The .py ending is important.

2009-03-31T06:21:00.000-07:00

Python Lexical Structure :

Following is a simple Python program. It shows the basic structure of many Python scripts follows:

1. Initialize variables (lines 1 – 3).

2. Do some processing (lines 4 – 5).

3. Make decisions and perform actions based on those decisions (lines 6 – 10).

name = “Jim”

age = 42

highschoolGPA = 3.89

enteredName = raw_input(“Enter your name: “)

print “\n\n”

if name == “Jim”:
print “Your age is “, age
print “You had a”, highschoolGPA, “GPA in high school”
if (highschoolGPA > 3):

print “You had better than a 3.0 GPA...good job!”

2009-01-13T22:19:00.000-08:00

Python Number and Expressions :

The interactive Python interpreter can be used as a powerful calculator.

Try the following : >>> 2 + 2

This should give you the answer 4. That wasn’t too hard.

Well, what about this : >>> 53672 + 235253 = 288925

Still not impressed? Admittedly, this is pretty standard stuff. (I’ll assume that you’ve used
a calculator enough to know the difference between 1+2*3 and (1+2)*3.)

All the usual arith- metic operators work as expected—almost. There is one potential trap here, and that is integer division (in Python versions prior to 3.0) : >>> 1/2 = 0

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Python Interactive Interpreter :

When you start up Python, you get a prompt similar to the following:

Python 2.5.1 (r251:54869, Apr 18 2007, 22:08:04)

[GCC 4.0.1 (Apple Computer, Inc. build 5367)] on darwin.

Type "help", "copyright", "credits" or "license" for more information. >>>

■Note: The exact appearance of the interpreter and its error messages will depend on which version you are using.

It’s an interactive Python interpreter.

Just try the following :

>>> print "Hello, world!"

When you press the Enter key, the following output appears : Hello, world! >>>

2008-12-31T22:44:00.000-08:00

Getting Started :

Of course, the first thing you need to do is install Python, if you don ’ t already have it. Installers are available for Windows, Macintosh, Linux, Unix, and everything from OpenVMS to the Playstation (no, I ’ m not kidding).

Obtaining Python and Installing It :

If you go to ' www.python.org/download ' you can find links to download the correct version of Python for your operating system. Follow the install instructions for your particular Python distribution — instructions can vary significantly depending on what operating system you are installing to.

What Version Number to Install :

Although the examples in this book should work for any Python version above 2.0, it is best to install the latest stable build for your operating system.

For Windows (which is the environment I primarily work in), the latest stable version is 2.51. There is an alpha build of Python 3.0 available as of this writing, but other than just looking at it for R & D enjoy.

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Integrated Development Environments (IDEs) for Python:

ActivePython is a Python distribution from ActiveState (http://www.activestate.com).

At its core, it’s the same as the standard Python distribution for Windows. The main difference is that it includes a lot of extra goodies (modules) that are available separately. It’s definitely worth a look if you are running Windows.

Komodo has been made open source, so free versions are also available.
Environment Description Web Site IDLE The standard Python environment

http://www.python.org/idle

Pythonwin Windows-oriented environment http://www.python.org/download/windows

ActivePython Feature-packed; contains Pythonwin IDE

http://www.activestate.com

Komodo Commercial IDE http://www.activestate.com3

Wingware Commercial IDE http://www.wingware.com

BlackAdder Commercial IDE and (Qt) GUI builder http://www.thekompany.com

Boa Constructor Free IDE and GUI builder http://boa-constructor.sf.net
Anjuta Versatile IDE for Linux/UNIX http://anjuta.sf.net
Arachno Python Commercial IDE http://www.python-ide.com
Code Crusader Commercial IDE http://www.newplanetsoftware.com
Code Forge Commercial IDE http://www.codeforge.com
Eclipse Popular, flexible, open source IDE http://www.eclipse.org
eric Free IDE using Qt http://eric-ide.sf.net
KDevelop Cross-language IDE for KDE http://www.kdevelop.org
VisualWx Free GUI builder http://visualwx.altervista.org
wxDesigner Commercial GUI builder http://www.roebling.de
wxGlade Free GUI builder http://wxglade.sf.net

2008-10-22T23:17:00.000-07:00

Brief Intro about Mobile Python :

Python is a dynamic object-oriented, open-source, computer-program-
ming language. It can be used for many kinds of software development,
for instance, to create stand-alone programs, scalable server software or
small scripts – Python’s roles are virtually unlimited. Python was created
by Guido van Rossum and is distributed under an OSI-approved, open-
source license that makes it free to use, even for commercial products.

Python is often used for prototyping and teaching introductory pro-
gramming classes. It can be learned in a few days and offers strong
support for integration with other languages and tools. Python comes
with an extensive standard library, thus its slogan is ‘Python – batteries
included’.

Python runs on most common and legacy platforms, for example,
Windows, Mac OS X, Linux/Unix, OS/2, Amiga and Palm OS. It also
runs on Nokia S60 2nd and 3rd Edition mobile phones – that is where
this book comes in. Python has also been ported to the Java and .NET
virtualmachines. It is an interpreted programming language that combines
remarkable power with clear syntax; it has modules, classes, exceptions,
high-level dynamic data types and dynamic typing.

Python for S60 brings the Python programming language to the S60
platform. Python for S60 is based on Python version 2.2.2. It supports
many of the Python Standard Library modules but also includes sev-
eral modules speciﬁc to the mobile platform, for example, native GUI
elements, Bluetooth, networking, GSM location information, SMS mes-
saging, access to the camera, and more.

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Adding New Section : Python

Mobile Python – or, more formally, Python for S60 (see Figure 1.1) –
empowers you to do fun and engaging stuff with your mobile phone.
You can start programming shortly after getting into this book. Being able
to see results quickly on the phone guarantees to bring inspiration and
makes programming these gadgets fun!

Development on the Symbian platform has been time-consuming in
the past and it has required in-depth knowledge of C++ or Java. Python
for S60 remedies this problem. It is easy to learn and takes only a few days
to get into most of its features. Novice programmers, artists and people
from creative communities can innovate and contribute applications to
the mobile space.

2008-09-30T06:52:00.000-07:00

Google AJAX Language API - Tools for translation and language detection

The API helps developers automatically translate content in their applications.

Users on these sites will have an easier time communicating across lingual boundaries.

The Language API provides both translation and language detection.

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XSLT :

The first and most well-developed face of XSL is a conversion tool known as XSLT.

The T stands for transformation, and that’s exactly what this part of XSL is designed to do — use a set of rules to transform (that is, convert) documents described by one set of elements into documents described by another set of elements.

2008-07-29T03:42:00.000-07:00

Development of an AJAX-enabled grid using ICallbackEventHandler, with operations which include sorting, paging and page length change.

The basic features of the gird are as follows (All operations are asynchronous)

Sort in ascending or in descending order by clicking on the arrows next to column name.

1.) Change current page.

2.) Change page length.

The server-Side functions are as follows
public string GetCallbackResult()

{

return result;

}

This function simply returns the result which we have put as innerHTML in the ShowResult function.

2008-06-27T01:46:00.000-07:00

What JavaScript libraries and frameworks are available?

There are many libraries/frameworks out there (and many more emerging) that will help abstract such things as all the nasty browser differences. Three good libraries are The Dojo Toolkit, Prototype, and DWR.

The Dojo Toolkit contains APIs and widgets to support the development of rich web applications. Dojo contains an intelligent packaging system, UI effects, drag and drop APIs, widget APIs, event abstraction, client storage APIs, and AJAX interaction APIs. Dojo solves common usability issues such as support for dealing with the navigation such as the ability to detect the browser back button, the ability to support changes to the URL in the URL bar for bookmarking, and the ability to gracefully degrade when AJAX/JavaScript is not fully support on the client. Dojo is the Swiss Army Knife of JavaScript libraries. It provides the widest range of options in a single library and it does a very good job supporting new and older browsers.

Prototype focuses on AJAX interactions including a JavaScript AJAX object that contains a few objects to do basic tasks such as make a request, update a portion of a document, insert content into a document, and update a portion of a document periodically. Prototype JavaScript library contains a set of JavaScript objects for representing AJAX requests and contains utility functions for accessing in page components and DOM manipulations. Script.aculo.us and Rico are built on top of Prototype and provide UI effects, support for drag and drop, and include common JavaScript centric widgets. If you are just looking to support AJAX interactions and a few basic tasks Prototype is great. If you are looking for UI effects Rico and Script.aculo.us are good options.

Yahoo UI Library is a utility library and set of widgets using the APIs to support rich clients. The utility library includes support for cross-browser AJAX interactions, animation, DOM scriptging support, drag and drop, and cross browser event support. The Yahoo UI Library is well documnented and contains many examples.

DWR (Dynamic Web Remoting) is a client-side and server-side framework that focuses on allowing a developer to do RPC calls from client-side JavaScript to plain old Java objects in a Java Enterprise Edition web container. On the server side DWR uses a Servlet to interact with the Java objects and returns object representations of the Java objects or XML documents. DWR will be easy to get up and running and plays well with other Java technologies. If you are looking for a client-side and server-side framework that integrates well use DWR.

Google Web Toolkit (GWT) is client/server framework provided by Google that allows a developer to write an AJAX application in pure Java. The GWT takes care of the details of generating all the client-side code using a Java-to-JavaScript compiler. One of the key benefits of the GWT Software Developer Kit (SDK) is that it allows you to debug your applications in what is known as GWT hosted mode using an embedded browser (IE on Windows and Mozilla/Gecko on Linux) that is tied to the toolkit. In GWT hosted mode you setup through the code and debug it as it is running on both the client and server. The GWT contains a default set of widgets and widget containers. An application is built by coding a set of widgets and containers together much like would be done in a Swing application. The GWT Software Developer Kit (SDK) is limited to Linux and Windows XP/2000 though the web applications it generates are compatible with the latest generation of the mainstream browsers.

There are many new and emerging libraries for JavaScript and this list only reviews some of the more common libraries. When making a choice choose the library which suites your needs the best. While it might be better to choose one, there is nothing stopping you from using more than one framework. For a more extensive list of client-side frameworks see: Survey of AJAX/JavaScript Libraries.

2008-06-27T01:43:00.000-07:00

What do I need to know to create my own AJAX functionality?

If you plan not to reuse and existing AJAX component here are some of the things you will need to know.

Plan to learn Dynamic HTML (DHTML), the technology that is the foundation for AJAX. DHTML enables browser-base realtime interaction between a user and a web page. DHTML is the combination of JavaScript, the Document Object Model (DOM) and Cascading Style Sheets (CSS).
JavaScript - JavaScript is a loosely typed object based scripting language supported by all major browsers and essential for AJAX interactions. JavaScript in a page is called when an event in a page occurs such as a page load, a mouse click, or a key press in a form element.
DOM - An API for accessing and manipulating structured documents. In most cases DOM represent the structure of XML and HTML documents.
CSS - Allows you to define the presentation of a page such as fonts, colors, sizes, and positioning. CSS allow for a clear separation of the presentation from the content and may be changed programmatically by JavaScript.

Understanding the basic request/response nature of HTTP is also important. Many subtle bugs can result if you ignore the differences between the GET and OIst methods when configuring an XMLHttpRequest and HTTP response codes when processing callbacks.

JavaScript is the client-side glue, in a sense. JavaScript is used to create the XMLHttpRequest Object and trigger the asynchronous call. JavaScript is used to parse the returned content. JavaScript is used to analyze the returned data and process returned messages. JavaScript is used to inject the new content into the HTML using the DOM API and to modify the CSS.

2008-06-27T01:31:00.000-07:00

What is OpenAjax?

OpenAjax represents the collection of technologies and approaches defined by the OpenAjax Alliance to promote open and interoperable Ajax-based Web technologies that in turn lead to long-term customer success with Ajax.

How OpenAjax Alliance is organized :

1. Steering Committee --

The members of the OpenAjax Alliance elect representatives from seven companies to positions on the OpenAjax Alliance Steering Committee. The Steering Committee manages the affairs of the OpenAjax Alliance on behalf of its member organizations. Among other things, the Steering Committee has final approval on the creation of working groups and specifications.

2. Working Groups --

The OpenAjax Alliance develops its Specifications and other published Material within Working Groups that are chartered and approved by its membership and Steering Committee. At this point, the alliance has the following Working Groups:
Interoperability Working Group - This group is responsible for technical activities in the general area of Ajax runtime interoperability. The key products coming out of this group include documents that provide the detailed definition of OpenAjax Conformance, such as the Specification for the OpenAjax Hub, management of the OpenAjax Registry, and development of OpenAjax Best Practices.

Marketing Working Group -

This group is responsible for the OpenAjax Alliance's communications, educational and promotional activities for fulfilling the Alliance's mission to accelerate customer success with Ajax, promote adoption of open and interoperable Ajax-based Web technologies, and help drive the future of the Ajax ecosystem. Among other things, this group produces the Alliance's white papers, oversees the development of its website, and drives the strategy, high-level definition and industry rollout of the term OpenAjax Conformance.

IDE Working Group -

This group is developing metadata standards for Ajax libraries in order to facilitate the integration of Ajax libraries into Ajax developer tools (i.e., IDEs).

Task Forces

The OpenAjax Alliance establishes task forces to investigate possible areas of new activity. The task forces are informal groups of interested members who perform relevant research and then produce recommendations for future alliance activities. Sometimes task forces are promoted into formally chartered working groups.

At this time, there are six active task forces:

Security Task Force, which is identifying key Ajax security issues and investigating related activities that the alliance might pursue ,

Mobile Ajax Task Force, which is investigating what OpenAjax Alliance might do to accelerate customer adoption and success with Ajax on mobile devices

Production Ajax Management Task Force, which is investigating what OpenAjax Alliance might do to help vendors and customers in the area of runtime performance monitoring

Searchability Task Force, which will investigate how to make current application state within an Ajax application discoverable and usable to search engines, perhaps by standardizing on particular approaches to URL fragment identifiers or parameters.

Runtime Advocacy / Lobbying Task Force, which will attempt to recruit a critical mass of Ajax toolkits and investigate ways that OpenAjax Alliance might be able to play an advocacy role to accelerate browser improvements that make Ajax applications work better.

Mashup Widgets/Gadgets Task Force, which will investigate a common metadata standard for Ajax-based mashup components such that (ultimately) the developers of the mashup components will be able to write-once and have it run anywhere.

2008-05-30T05:46:00.000-07:00

AJAX Limitation :

As a developer, you’re probably well aware of this issue which is commonly occur due to cached data.

AJAX is not unique when it comes to these type of issues .

2008-04-30T07:06:00.000-07:00

Who’s Using Ajax :

Google is making a huge investment in developing the Ajax approach. All of the major products Google has introduced over the last year — Orkut, Gmail, the latest beta version of Google Groups, Google Suggest, and Google Maps — are Ajax applications. (For more on the technical nuts and bolts of these Ajax implementations, check out these excellent analyses of Gmail, Google Suggest, and Google Maps.) Others are following suit: many of the features that people love in Flickr depend on Ajax, and Amazon’s A9.com search engine applies similar techniques.

2008-04-30T07:03:00.000-07:00

Q. Is Ajax just another name for XMLHttpRequest?

A. No. XMLHttpRequest is only part of the Ajax equation. XMLHttpRequest is the technical component that makes the asynchronous server communication possible; Ajax is our name for the overall approach described in the article, which relies not only on XMLHttpRequest, but on CSS, DOM, and other technologies.

Q. Is Ajax a technology platform or is it an architectural style?

A. It’s both. Ajax is a set of technologies being used together in a particular way.

Q. What kinds of applications is Ajax best suited for?

A. We don’t know yet. Because this is a relatively new approach, our understanding of where Ajax can best be applied is still in its infancy. Sometimes the traditional web application model is the most appropriate solution to a problem.

2008-04-30T06:58:00.000-07:00

How to build an Ajax website :

You need for some wrapper. Your JavaScript program, integrated into a web page, sends request to the server to load files for rebuilding of pages. The received documents are processed with Dom's methods or XML parsers and the data are used to update the pages.

2008-03-31T21:30:00.000-07:00

Web 2.0 Technologies :

Dynamic User Interfaces – Dynamic user interfaces refer to a web application's responsiveness and its ability to interact more dynamically with actions you take on its web pages. Using Asynchronous JavaScript and XML (Ajax) technologies to build more interactive user interfaces, Ajax enables web application users to asynchronously update and retrieve data from a server without having to wait for a screen refresh. Of particular importance here in the Java space are Sun Microsystems' jMaki and DynaFaces technologies.
- jMaki tools enable developers to wrap any widget in a JSP tag or a JSF component so the widget can be easily implemented in a Web application.
- DynaFaces focuses on enabling JSF developers to Ajax-enable the JSF components they already use.
In addition to jMaki and Dynafaces, a third-party JavaScript library, called Dojo, is also included in the Sun WDP.
Lightweight Programming Models – Platform-agnostic scripting languages are becoming increasingly popular with web application developers because of their flexibility and because they often allow for more rapid development than previous coding techniques. While no one scripting language is dominant at this time, Ruby and JavaScript are among the most popular. In response to this popularity, the Sun WDP includes technology from the Phobos project, which provides an application framework that enables you to develop web applications entirely in a scripting language, while still providing access to the entire Java EE stack. Phobos currently supports only JavaScript, but support for other scripting languages is planned with the help of JSR 223 (Scripting for the Java Platform).
Lightweight Web Services – The Representation State Transfer Technology (REST) architectural model emphasizes building web services that can be accessed as resources by means of the common HTTP GET, POST, PUT, and DELETE operations. The technologies included in the Sun WDP that facilitate REST style coding are:
- ROME – (RSS and Atom Utilities) API for processing and generating syndication feeds
- WADL – (Web Application Description Language) Web services description language like WSDL, but designed for REST-based Web services by supporting the base set of HTTP methods for accessing resources
- Atom – XML-based format for syndication feeds and a publishing protocol that provides CRUD (Create, Read, Update, Delete) support for REST-based Web services

2008-03-31T21:07:00.000-07:00

Who’s Using Ajax

These projects demonstrate that Ajax is not only technically sound, but also practical for real-world applications. This isn’t another technology that only works in a laboratory. And Ajax applications can be any size, from the very simple, single-function Google Suggest to the very complex and sophisticated Google Maps.

2008-02-29T04:14:00.001-08:00

Accessibility :

Non-Ajax users would ideally continue to load and manipulate the whole page as a fall back, enabling the developers to preserve the experience of users in non-Ajax environments (including all relevant accessibility concerns) while giving those with capable browsers a much more responsive experience.

For this reason it is advised to first develop a full application without Ajax, and implement Ajax enhancements as an addition only.

2008-01-29T00:39:00.000-08:00

Drawbacks of Ajax :

- If JavaScript is not activated, Ajax can't works. The user must be asked to set JavaScript from within options of the browser, with the "no-script" tag.

- Since data to display are loaded dynamically, they are not part of the page, and the keywords inside are not used by search engines.

- The asynchronous mode may change the page with delays (when the processing on the server take some times), this may be disturbing.

- The back button may be deactivated (this is not the case in examples provided here). This may be overcomed.

2007-12-20T23:28:00.000-08:00

AJAX TiP:

Like DHTML, LAMP, and SPA, "Ajax" is not a technology in itself, but a term that refers to the use of a group of technologies.

2007-11-12T01:32:00.000-08:00

The AJAX sequence diagram that shows how the XMLHttpRequest is used.

Image URL Info. http://www.modelworks.com/images/ajax.png

2007-11-12T01:25:00.000-08:00

Uses of AJAX

AJAX has many potential uses. Here are a few of them:

Updating page information
Real-time data validation
Obtaining data for a control
Responding to server events
Pushing data to the client
Real-time interaction
Real-time monitoring
Auto completion

2007-11-12T01:23:00.000-08:00

AJAX requires both client side and server side code. This means that you have more technology to master. It also means that you will have to rely on client side technology which you do not control. At a minimum it means knowing DHTML, JavaScript and at least one server side technology.

2007-10-30T23:22:00.000-07:00

The AJAX Toolkit Framework (ATF) Project URL info. :

http://www.eclipse.org/proposals/atf/

2007-10-30T23:17:00.000-07:00

The Zimbra Ajax Toolkit :

Zimbra is contributing to the Open Ajax Initiative by providing open access to the Zimbra Ajax Toolkit (AjaxTK).

Zimbra has used AjaxTK to push the envelope of what we think of as a Web page by developing a complete online Collaboration Suite, including enterprise-class e-mail, calendar, and contacts.

The AjaxTK squeezes the responsiveness gap between a Web-based application and a standard desktop-based application to near zero.

Dojo Documentation URL info. :

http://files.zimbra.com/website/docs/Zimbra%20AJAX%20TK%20Whitepaper.pdf

2007-10-30T23:14:00.000-07:00

The Dojo Ajax Toolkit :

Is a runtime tool which will be supported in Eclipse's Ajax Toolkit Framework (ATF).

Dojo is a community project designed to unify the efforts of the JavaScript and Dynamic Hypertext Markup Language (DHTML) communities in a single direction by building a standard JavaScript library.

The community realized it wouldn't get far without people working together, so three separate predecessor tool kits were unified to form the Dojo Foundation, which owns and maintains the code. Dojo has several optional packages, including an Ajax edition; an I/O edition; and a "Kitchen Sink" edition, which includes the entire tool set.

Dojo Documentation URL info. :
http://dojotoolkit.org/docs

2007-10-30T23:08:00.000-07:00

Eclipse's Ajax Toolkit Framework :

Open Ajax Initiative components

2007-07-01T23:25:00.000-07:00

Hidden Frames in AJAX :--

This Technique is a longstanding trick of developers to return information from the server
but keep it invisible to the user.

It uses a standard frameset with two frames to open two separate pages (or more if required),
the first being visible to the user and the second being made invisible by setting its width or height to zero.

The hidden frame can be used to send requests and retrieve data from the server,
but the data is placed in the visible frame only when needed.

2007-05-29T02:40:00.000-07:00

Constituent technologies

The Ajax technique uses a combination of:

XHTML (or HTML) and CSS, for marking up and styling information.
The DOM accessed with a client-side scripting language, especially ECMAScript implementations such as JavaScript and JScript, to dynamically display and interact with the information presented.
The XMLHttpRequest object is used to exchange data asynchronously with the web server. In some Ajax frameworks and in certain situations, an IFrame object is used instead of the XMLHttpRequest object to exchange data with the web server, and in other implementations, dynamically added <script> tags may be used.
XML is sometimes used as the format for transferring data between the server and client, although any format will work, including preformatted HTML, plain text, JSON and even EBML. These files may be created dynamically by some form of server-side scripting.

2007-04-18T09:03:00.000-07:00

Bandwidth usage:-

Ajax web pages can appear to load relatively quickly since the payload coming down is much smaller in size.

2007-03-01T05:18:00.000-08:00

AJAX Data Insertion:--

Using Ajax is all about inserting fresh data into a page without having to
reload that page, and using the Dynamic HTML (DHTML) technique of inserting
text into a " div " or a " span " is very popular. Want to display some new
data? Fetch it from the server, pop it into a " div ", and pow!, there you are.
The " div " element is the most popular, but don’t forget that it’s a block element
and so takes up its own line(s) in the browser. If you want to place new
text inline, consider " span ".

2007-02-28T01:53:00.000-08:00

AJAX CHAT:--

Ajax excels at updating Web pages without refreshing the displayed
page, it’s a great choice for Web-based chat programs, where many users can
chat together at the same time.

2007-01-19T07:49:00.000-08:00

AJAX:-

Google

2006-10-17T07:57:00.000-07:00

What AJAX framework do you recommend for PHP applications?

SAjax, NAjax, FAjax.
All of them are ok, but it it best to make your own to suit your needs.

2006-10-17T07:54:00.000-07:00

What are the different frameworks available In AJAX ?

A good framework that I have seen is "Zephyr".
It is used with php and seems to be very easy to use.

You can get it from here http://zephyr-php.sourceforge.net

2006-09-18T07:07:00.000-07:00

Pros of AJAX:-

1).Bandwidth utilization

2).Interactivity

2006-08-30T07:36:00.000-07:00

What are the different frameworks available In AJAX ?

A good framework that I have seen is "Zephyr".
It is used with php and seems to be very easy to use.

You can get it from here http://zephyr-php.sourceforge.net

2006-07-13T07:07:00.000-07:00

How does it works:-

Ajax uses a programming model with display and events. These events are user actions, they call functions associated to elements of the web page.Interactivity is achieved with forms and buttons. DOM allows to link elements of the page with actions and also to extract data from Xml files provided by the server.

To get data on the server, XMLHttpRequest provides two methods:- open: create a connection.- send: send a request to the server.Data furnished by the server will be found in the attributs of the XMLHttpRequest object:- responseXml for a Xml file or- responseText for a simple text.Take note that a new XMLHttpRequest object has to be created for each new file to load.

We have to wait for the data to be available to process it, and in this purpose, the state of availability of data is given by the readyState attribute of XMLHttpRequest.

States of readyState follow (only the last one is really useful): not initialized.

1: connection etablished.
2: request received.
3: answer in process.
4: finished.

2006-07-13T07:04:00.000-07:00

What is Ajax in depth?

Ajax is a set of technologies, supported by a web browser, including these elements:
Html and CSS for presenting.

JavaScript (ECMAScript) for local processing, and DOM (Document Object Model) to access data inside the page or to access elements of Xml file read on the server (with the getElementByTagName method for example)...

The XMLHttpRequest class read or send data on the server asynchronously. optionally...
The DomParser class may be used PHP or another scripting language may be used on the server.

XML and XSLT to process the data if returned in Xml form.

SOAP may be used to dialog with the server. The "Asynchronous" word, means that the response of the server while be processed when available, without to wait and to freeze the display of the page.

2006-07-13T07:03:00.000-07:00

Why to use Ajax ?

Mainly to build a fast, dynamic website, but also to save resources.For improving sharing of resources, it is better to use the power of all the client computers rather than just an unique server and network. Ajax allows to perform processing on client computer (in JavaScript) with data taken from the server. The processing of web page formerly was only server-side, using web services or Php scripts, before the whole page was sent within the network.But Ajax can selectively modify a part of a page displayed by the browser, and update it without the need to reload the whole document with all images, menus, etc...For example, fields of forms, choices of user, may be processed and the result displayed immediately into the same page.

2006-07-13T07:02:00.000-07:00

Brief history of Ajax:-

Ajax is only a name given to a set of tools that were previously existing.The main part is XMLHttpRequest, a class usable in JavaScript , that was implemented into Internet Explorer since the 4.0 version.The same concept was named XMLHTTP some times, before the Ajax name becomes commonly used.The use of XMLHttpRequest in 2005 by Google, in Gmail and GoogleMaps has contributed to the success of this format. But this is the name Ajax itself that made the technology so popular.

2006-07-13T07:00:00.000-07:00

JavaScript and Server Technology Independent Frameworks:-

Many AJAX frameworks and libraries rely solely upon JavaScript and contain no server components and therefore server technology dependencies. Such AJAX libraries and frameworks include TIBCO General Interface, dojo Toolkit, MochiKit, and JackBe. Such frameworks are agnostic as to what server side technology you choose to use. Usually such frameworks are optimized to consume XML, though JSON is becoming popularized as well. Even Microsoft Atlas is, in part, positioned as having JavaScript libraries that can run without dependence on its .NET servers (though Altas perhaps works best with .NET services behind it).

2006-07-13T06:57:00.000-07:00

Ajax Framework:-

Ajax is a technology to build dynamic web pages on the client side. Data is read from the server or sent to the server by JavaScript requests. However, some processing at the server side is required to handle requests, i.e., finding and storing the data. This is accomplished more easily with the use of a framework dedicated to process Ajax requests. In the article that coined the "Ajax" term, J.J. Garrett describes the technology as "an intermediary...between the user and the server."

This Ajax engine is intended to suppress waiting for the user when the page attempts to access the server. The goal of the framework is to provide this Ajax engine and associated server and client-side functions.

2006-07-13T06:55:00.000-07:00

What's AJAX?

AJAX (Asynchronous JavaScript and XML) is a newly coined term for two powerful browser features that have been around for years, but were overlooked by many web developers until recently when applications such as Gmail, Google Suggest, and Google Maps hit the streets.

The two features in question are that you can:

A). Make requests to the server without reloading the page

B). Parse and work with XML documents