Ext (javascript library) - AbsoluteAstronomy.com

Ext JS is a JavaScript

JavaScript

JavaScript is a prototype-based scripting language that is dynamic, weakly typed and has first-class functions. It is a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles....

library for building interactive web application

Web application

A web application is an application that is accessed over a network such as the Internet or an intranet. The term may also mean a computer software application that is coded in a browser-supported language and reliant on a common web browser to render the application executable.Web applications are...

s using techniques such as Ajax

Ajax (programming)

Ajax is a group of interrelated web development methods used on the client-side to create asynchronous web applications...

, DHTML

Dynamic HTML

Dynamic HTML, or DHTML, is an umbrella term for a collection of technologies used together to create interactive and animated web sites by using a combination of a static markup language , a client-side scripting language , a presentation definition language , and the Document Object Model.DHTML...

and DOM

Document Object Model

The Document Object Model is a cross-platform and language-independent convention for representing and interacting with objects in HTML, XHTML and XML documents. Aspects of the DOM may be addressed and manipulated within the syntax of the programming language in use...

scripting.

Originally built as an add-on library extension of YUI by Jack Slocum, Ext includes interoperability with jQuery

JQuery

jQuery is a cross-browser JavaScript library designed to simplify the client-side scripting of HTML. It was released in January 2006 at BarCamp NYC by John Resig...

and Prototype

Prototype Javascript Framework

The Prototype JavaScript Framework is a JavaScript framework created by Sam Stephenson in February 2005 as part of the foundation for Ajax support in Ruby on Rails. It is implemented as a single file of JavaScript code, usually named prototype.js...

. Beginning with version 1.1, Ext retains no dependencies on external libraries, instead making their use optional.

GUI controls

Ext JS includes a set of GUI-based form controls (or "widgets") for use within web applications:

text field and textarea input controls
date fields with a pop-up date-picker
numeric fields
list box and combo boxes
Combo box
A combo box is a commonly used graphical user interface widget . It is a combination of a drop-down list or list box and a single-line textbox, allowing the user to either type a value directly into the control or choose from a list of existing options.Combo boxes are typically applied to provide...
radio and checkbox controls
html editor control
grid control (with both read-only and edit modes, sortable data, lockable and draggable columns, and a variety of other features)
tree control
tab panels
toolbars
desktop application-style menus
region panels to allow a form to be divided into multiple sub-sections
sliders
flash charts

Many of these controls are able to communicate with a web server using Ajax.

Application support

Ext JS includes web application support with features such as:

modal dialog boxes
interactive user-input validation prompts
state management

Other features include a DOM selector class allowing operations to be performed on elements within the page, data stores that can be used to manage data, and classes to create and manage data in JSON

JSON

JSON , or JavaScript Object Notation, is a lightweight text-based open standard designed for human-readable data interchange. It is derived from the JavaScript scripting language for representing simple data structures and associative arrays, called objects...

and XML formats.

Ext JS 2.0

Ext JS version 2.0 was released on 4 December 2007. This version was promoted as providing an interface and features more similar to those traditionally associated with desktop applications. Also promoted were the new user documentation, API documentation, and samples.

Ext JS 2.0 did not provide backward compatibility with version 1.1. A migration guide was developed to address this.

Ext JS 3.0

Ext JS version 3.0 was released on 6 July 2009. This version added communication support for REST

Representational State Transfer

Representational state transfer is a style of software architecture for distributed hypermedia systems such as the World Wide Web. The term representational state transfer was introduced and defined in 2000 by Roy Fielding in his doctoral dissertation...

and a new Ext.Direct server side platform. New flash charting and ListView elements were added to the standard display components. It was backwards compatible with version 2.0 code.

Ext JS 4.0

Version 4.0 of the Ext framework was released on April 26th, 2011. It includes a completely revised class structure, a revised data package, an animation and drawing package that uses SVG

Scalable Vector Graphics

Scalable Vector Graphics is a family of specifications of an XML-based file format for describing two-dimensional vector graphics, both static and dynamic . The SVG specification is an open standard that has been under development by the World Wide Web Consortium since 1999.SVG images and their...

and VML

Vector Markup Language

Vector Markup Language is a deprecated XML language used to produce vector graphics.VML was submitted as a proposed standard to the W3C in 1998 by Autodesk, Hewlett-Packard, Macromedia, Microsoft, and Visio. Around the same time other competing W3C submissions were received in the area of web...

, and revised charting and theming. It also includes an optional architecture that provides a Model-View-Controller

Model-view-controller

Model–view–controller is a software architecture, currently considered an architectural pattern used in software engineering. The pattern isolates "domain logic" from the user interface , permitting independent development, testing and maintenance of each .Model View Controller...

style of code organization.

Sencha

On 15 June 2010, the merger of Ext JS with JQTouch

JQTouch

jQTouch is an Open Source JQuery plugin with native animations, automatic navigation, and themes for mobile WebKit browsers like iPhone, G1 , and Palm Pre...

and Raphaël

Raphaël (JavaScript Library)

Raphaël is a cross-browser JavaScript library that draws vector graphics for web sites. It will use SVG for most browsers, but will use VML for older versions of Internet Explorer...

was announced forming a new organisation called Sencha Inc..
Ext JS continues to be available as a main product on the new Sencha website together with Sencha Touch, Ext GWT, Ext Designer, Sencha Animator and Ext Core.

License history

YUI-Ext was available under the BSD license. In 2008 the open source license associated with Ext was changed. In version 2.0.2, the authors stated that Ext was available under an LGPL-style license as long as you "plan to use Ext in a personal, educational or non-profit manner" or "in an open source project that precludes using non-open source software" or "are using Ext in a commercial application that is not a software development library or toolkit". This was no longer the case with Ext 2.1. Some people claimed that the license conditions as the authors described it stood while others claimed that clause 7 of the LGPL-style license enabled the software to be used by all regardless of Ext's conditions. The Ext authors claim that section 7 of the LGPL as it is worded does not apply to "conditions" which their license requires before distribution under the LGPL is permitted as opposed to "additional restrictions" which section 7 allows a distributor to remove.

On 20 April 2008, Ext 2.1 was released under a new dual license which allowed the options of the full GPL 3.0 license or a commercial license.

The change in license over time, from a permissive open source license to a restrictive dual license, caused controversy in the Ext user community.