XUL  -  Building Graphical Interfaces

XUL means for "XML-based User interface Language". This is a semantic extending XML for building graphical interfaces . Has been created by Mozilla in 1999.

Features of XUL

• The code is interpreted.
• JavaScript code may be embedded into xml to define functions called by events.
• Uses bitmap graphics.
• Events (a mouse click for example) are properties of tags and tags are components of the interface.
• Style properties are defined inside standard CSS files.
• Component (mainly the "widgets", graphical components) may be define by user, in XBL or XPF files.
• The RDF format is user to store and deliver texts, for localization for example.
• XPCom is used for the wrapper between XUL and libraries written in various programming languages.

Why to use XUL?

XUL allows to create cross-platform, graphical user interfaces for standalone applications.
Mozilla has developped Prism, a tool for accessing XUL Web applications from the desktop.
It is a standard and portable format, working on any operating system, but is rather difficult to use.

Sites and tools

• Xul.fr
  Site dedicated to XUL and Ajax.
• Comparisons
  Comparing XAML and XUL and other XML graphical interface languages.
• XulRunner
  Download the runtime.
• Installing
  How to install a XUL application.
• Mozilla
  Official website.
• XUL tutorial
  With examples and source code. See also the tutorial from Mozilla, the creator of the language that is similar to that of XULPlanet.

Sample code

<?xml version="1.0">
<windows width="600 height="480">
  <description>
    Hello World!
  </description>
</windows>

<button 
   label="Close" 
   oncommand="window.close()"
/>