Chapter 17. GNOME
One of the two popular desktop
environments used with Linux, GNOME is provided as the default
desktop for Red Hat, Debian, and several other popular distributions.
As a graphical environment, GNOME provides users with a highly
customizable user interface and consistent functionality of common
GUI features such as menus, toolbars, and buttons. In addition, it
offers users a growing set of native applications to create a
productive computing system. The number and quality of applications
are a testament to the developer-friendly GNOME libraries; many GNOME
technologies are also used in nongraphical or totally unrelated
software. GNOME is distributed with most Linux distributions, and you
can also get it from the GNOME web site (http://www.gnome.org) or from Ximian
(http://www.ximian.com), a
company that specializes in the GNOME desktop. GNOME stands for "GNU Network Object
Model Environment," and although the name is
admittedly obscure, it does point to one of GNOME's
core technologies: its CORBA-based objects. CORBA (Common Object Request
Broker Architecture) specifies methods that allow interaction among
applications through the sharing and embedding of component objects.
For example, a spreadsheet created by Gnumeric (a GNOME spreadsheet
program) can be placed as an object into an AbiWord document, and the
Nautilus file browser can display images, web pages, and so forth by
embedding an image viewer and HTML display engine. GNOME uses two
libraries to do this: ORBit, (http://orbit-resource.sourceforge.net), which
provides an Object Request Broker (ORB), and
Bonobo
(http://developer.ximian.com/articles/whitepapers/bonobo),
which is designed to simplify the task of creating reusable software
components and compound documents. This edition of Linux in a Nutshell covers a
GNOME desktop based on the GNOME 2 platform, which is included
in Red Hat 8.0, Mandrake 9.0, and SuSE 8.1, among other
distributions. The new platform differs from the previous version,
GNOME 1.4, in a number of significant ways. Overall, the new platform
has brought increased performance and stability, more coherent and
powerful developer tools, and a friendlier, simpler interface. You do not need to be familiar with earlier versions of GNOME to use
GNOME 2. If you are familiar with earlier versions and want to know
what's new, or if you are curious about the history
of the project, see Section 17.5 at
the end of this chapter for additional background information.
17.1. Desktop Overview
Figure 17-1 shows the default GNOME desktop. The
left side of the screen contains icons that are shortcuts to open
applications, files, or URLs. The top icon is a link to the
user's home folder; when double-clicked, it launches
the Nautilus file manager to display the folder's
contents. The other icons include shortcuts to the floppy drive and
CD-ROM and links to web pages. In general, double-clicking on an icon
leads to the most logical operation, so clicking folder icons
displays folder contents, clicking application icons launches
applications, and clicking a file opens the file in its most
appropriate application (see Section 17.4.4.2 for information on how to
choose which one). A button or icon you can press to start an
application is called a
launcher. You can
drag and drop the icons around the desktop to arrange them as you
like, or drag them onto the Trash icon to get them out of your way.
Figure 17-1. The GNOME desktop
You can also right-click on any blank space in the desktop and get a
context menu that allows you to:
-
Open a new file manager window.
-
Create a new folder.
-
Create an application launcher.
-
Open a new terminal window.
-
Run scripts or executable files you place in your scripts folder
(~/.gnome2/nautilus-scripts).
-
Clean up the icons on the desktop.
-
Copy, paste, or cut selected files.
-
Change your desktop background.
-
Display the contents of any mounted disk in the file manager.
The bars across the top and bottom of the screen are called
panels. Some
distributions and configurations use only one, and others use more
than two. GNOME allows you to create a variety of
panels and choose their placement, size, and behavior. The one at the
top, called the menu panel, is perhaps the most common and important.
It may be slightly different in some distributions of GNOME, but it
generally consists of two menus on the left, and a clock and
application switcher on the right. Some systems may also include
other small applications, called
applets; see Section 17.2.3 for more information.
If you do not have a menu panel, the desktop probably offers the
GNOME menu, which is similar to the Start
menu in Microsoft Windows. On most systems, it appears in the lower
left corner and is designated with a GNOME foot logo, earning it the
nickname "the foot menu." In Red
Hat 8.0, click the red hat to get the same menu with a list of
applications, help, and a few other tools, plus the logout and
screen-locking tools. If you want to add this GNOME menu to a panel,
right-click on any blank space in the panel and select Add to Panel
→ GNOME Menu.
In general, the panel is a primary means of finding and opening
applications and managing your desktop. You can add buttons to the
panel to launch any application on your system; you can also include
small applications, called applets, in the panel. For more
information, see Section 17.2.
GNOME allows you an enormous number of configuration options for your
desktop environment. You can right-click on just about anything and
get a pop-up menu (called a context
menu) containing specific actions for that
item and a way to configure its properties. General configuration
settings are contained in the GNOME Control Center. You can access
this tool by selecting System and then Settings in your menu panel
(on some systems, look for Desktop Preferences under the Programs or
Applications menu). For more information about settings, see Section 17.4.
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Copyright © 2003 O'Reilly & Associates. All rights reserved.
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