Firefox Hacks [Electronic resources] نسخه متنی

8.1. Hacks 84-90

This chapter describes how to create and deploy Firefox enhancements
properly. Enhancements include skins, themes, extensions, and
applications. This chapter covers the creation of JAR and XPI files,
their contents, and the web site features that are used to deliver
them.

Firefox browser windows (and other Firefox windows) can be compared
to the command-line environment. Just as a command-line interface can
be used to start many different programs, so too can Firefox windows.
They are good places from which to launch other applications or
enhancements. Such applications can be started through
Firefox's menu system, the keyboard, or the mouse,
and they can be trivial or complex. They can be highly integrated
with Firefox, like extensions, or they can be mostly separate, like
the DOM Inspector.

The Firefox web browser is also Internet-enabled and is therefore a
kind of application portal for applications that are local, remote,
or remotely installed. The concept of being able to launch your own
application (or simple feature) from a widely used and free
application portal like Firefox is very attractive to some service
providers. Firefox provides them with an automatic deployment
mechanism.

To build a quality enhancement that can be invoked from a Firefox
window, the content that makes up that enhancement must be built out
of chrome
technology:
XUL, CSS, JavaScript, and images. That content must then be annotated
and bundled up correctly, using RDF, so that when Firefox first gets
itusually through a URLall the right bookkeeping is
done in the small text files that Firefox maintains. With that
bookkeeping in place, the extension (or application or theme) can
reliably be made available to the end user.

This chapter is mostly concerned with explaining how that bookkeeping
is done correctly. Chapter 7 takes a more
immediate look at how to build chrome content. The introductory
concepts described in [Hack #75]
also apply to this chapter. The main difference is that this chapter
requires more organization and more discipline.