Ext is a client-side, JavaScript framework for building web applications. In early 2006, Jack Slocum began working on a set of extension utilities for the Yahoo! User Interface (YUI) library. These extensions were quickly organized into an independent library of code and distributed under the name "yui-ext." In the fall of 2006, Jack released version .33 of yui-ext, which turned out to be the final version of the code under that name (and under the open source BSD license). By the end of the year, the library had gained so much in popularity that the name was changed simply to Ext, a reflection of its maturity and independence as a framework. A company was formed in early 2007, and Ext is now dual-licensed under the GPL and a commercial license. The library officially hit version 1.0 on April 1, 2007.
Please take a look here.
As a client-side framework, Ext can run against any server platform that can process POST requests and return structured data. Common choices include PHP, Java, .NET and many more. There are server-side frameworks available for most popular platforms that will make your life much easier when programming under the AJAX application model that Ext uses.
Up until version 1.0.1a, Ext required one of the following base libraries to be included: YUI, jQuery or Prototype/Script.aculo.us. Ext contains adapters that provide some of the basic plumbing utilities from those libraries, including Ajax support, animation, DOM manipulation, event handling, etc. Beginning with version 1.1, Ext includes a native Ext adapter, so the external libraries are no longer required.
Your choice of base libraries/adapters will most likely be driven by whether or not you already use an external library for something that Ext does not provide. For example, YUI includes some components like a history manager that Ext does not provide. (Ext 2.2 now has a history component) In that case, you may want to include the YUI adapter. Or if you have already invested in a library in an existing application, but want to add Ext to it, you might consider the adapter for that library to keep the code size smaller. If you do not have either of those needs, the Ext adapter will provide the smallest footprint and most compatible support. Note: since the non-Ext adapters rely on external libraries, not all functions are guaranteed to be supported or bug-free.
This same list is also included with the Ext download in the root folder in a file called INCLUDE_ORDER.txt. All Ext adapter files (and ext-base.js) can be found in the \adapters folder in the release. The libraries are listed in order of recommendation. Note: At the present time, Prototype/Scriptaculous support should still be considered experimental as there are several known bugs and unsupported functions that can cause problems with Ext.
| Base Library | Include Order | Get Library |
|---|---|---|
| Ext Standalone | ext-base.js ext-all.js (or your choice of files) | http://www.extjs.com/download |
| Yahoo! UI (.12+) | yui-utilities.js (or your choice of YUI base files) ext-yui-adapter.js ext-all.js (or your choice of files) | http://developer.yahoo.com/yui/ |
| jQuery (1.1+) | jquery.js jquery-plugins.js // required jQuery plugins ext-jquery-adapter.js ext-all.js (or your choice of files) | http://jquery.com/ http://docs.jquery.com/Plugins |
| Prototype (1.5+) / Scriptaculous (1.7+) | prototype.js scriptaculous.js?load=effects (or whatever you want to load) ext-prototype-adapter.js ext-all.js (or your choice of files) | http://www.prototypejs.org/ http://script.aculo.us/ |
Note for YUI users: Ext already includes yui-utilities.js, which is a convenience file containing the base YUI utilities (YAHOO, Event, Dom, Animation and Connection). If you do not otherwise use YUI, this should be sufficient for your needs — it is not guaranteed to be up-to-date with the most current release of YUI, but it is guaranteed to work correctly with Ext. If you need something in the most current release of YUI, you may need to supply your own copy of the utility files that you need.
As specified here: Regarding SVN. Access to the Ext SVN (Subversion) repository is available to support subscribers only. The only source code that you can download is the latest code officialy released by the ExtJS team and is accessible from here.