home | O'Reilly's CD bookshelfs | FreeBSD | Linux | Cisco | Cisco Exam  

Running Linux, 4th Ed.Running Linux, 4th Ed.Search this book

11.4. The GNOME Desktop Environment

The GNOME desktop environment was conceived in 1999 as an alternative to KDE, with its roots in the GPL and LGPL. Like KDE, GNOME had the goal of providing modern, easy-to-use applications that work with each other and with existing X applications.

We're going to give you a tour of GNOME the way it commonly looks, but you should be aware that it's a general-purpose framework with really unlimited flexibility. For example, we show the current window manager, Sawfish, but you can install a different window manager with a completely different behavior and appearance. The GNOME libraries, as well as the X libraries, underlie all the components, and have appeared in command-line and even server-based applications as well as the graphical desktop. In addition, the GNOME project has developed some powerful applications in typical areas of office work, such as spreadsheets and address books. Any X application can run under GNOME (although it has to be written with the GNOME framework to use the most powerful desktop features, such as the virtual filesystem and themes). In particular, a lot of KDE applications work very nicely on GNOME, and vice versa.

Of course, for our purposes, the interesting parts are the core desktop and its associated applications. In the next sections, we'll go over the GNOME look and feel, talk a little bit about the customization options it offers to you, and then give a quick tour of major applications, such as Evolution and Gnumeric. But first, you'll want to make sure you have the software and that it's up to date.

11.4.1. Installing and Updating GNOME

Most Linux distributions include GNOME, but if you haven't installed it yourself, or if you want a newer version, you can visit http://gnome.org for source and http://ximian.com for convenient binaries. Ximian offers a preassembled distribution of the desktop for the most common Linux distributions. To install it, do the following:

  1. Open a terminal window

  2. Use the su command to become root

  3. Run the command: lynx -source http://go-gnome.com |sh

The command downloads a graphical installation program, shown in Figure 11-8. Follow the on-screen instructions, and in a few minutes you'll have everything installed. The installer will ask you to log out, and when you log back in, a wizard will guide you through the process of setting some preferences for your new desktop.

Figure 11-8

Figure 11-8. Installing GNOME

Updates are also easy in GNOME: the Red Carpet utility (red-carpet at the command line, or click System, and then Get Software from the GNOME menu panel) checks for updates to your entire system, including GNOME, and offers to install them for you. Software is divided into neat channels — one for your distribution, another for the GNOME desktop, another for additional software like the Opera web browser or the CodeWeavers WINE tools. When you subscribe to a channel, Red Carpet will check for updates to the software that's on your system from that channel. You can also add or remove software in each channel by choosing the Update, Install, or Remove buttons along the upper-right corner of the channel windows.

11.4.2. Core Desktop Interface

The GNOME desktop is designed to be familiar to anyone who has used a computer before. Although you can change the settings in almost any way, a typical installation will have a desktop with icons on it and a panel along the top and bottom. The panels are among the most important GNOME tools because they are so versatile and they allow a wide range of interactions with your system. Panels can exist along one edge of your screen, like the Windows control panel; along a portion of it, like the Macintosh Control Strip; in an arbitrary position on the screen, like the NeXT dock; or in a combination of styles. They can contain menus, buttons, and small applications or applets, such as clocks, window lists, network and system monitors, and even tiny games.

A few features differ slightly from other graphical interfaces, such as the ability to have multiple virtual workspaces (familiar to fvwm users, but not many others) and some of the bells and whistles in the Nautilus file manager. We'll cover some of them in passing, but the majority of them are small enough that you can discover them on your own.

Here is a quick explanation of how to perform the most common tasks. Once you get the hang of these, you can probably guess how to do anything else.

Move items around on the desktop
Click and drag with the left mouse button.

Move items in the panel
Clicking and dragging with the left mouse button works for launchers, but for some applets, the left mouse button is used to control the applet. In that case, middle-click and drag. This is also the case for moving windows by their borders — left-click will expand the window, but middle-click lets you move it.

Organize items on the desktop
Right-click the desktop background and select Clean Up by Name. Items will be arranged in alphabetical order, with two exceptions: the first item, in the upper left, is always your home directory, and the last item in the list is always the Trash folder.

Open or activate an item on the desktop
Double-click it. If you double-click a folder icon, it will open the folder in the Nautilus file management tool. If you double-click a spreadsheet document, the Gnumeric spreadsheet will start and open the document.

Open or activate an item in the panel
Click once with the left button.

Get a list of options or set preferences for any object
Click with the right mouse button to get a menu of available options for any object. For example, you can change the desktop background by right-clicking it and choosing Change Desktop Background. More general preferences are available in the GNOME Control Center, which you can access by choosing System Figure Settings or Applications Figure Desktop Preferences, or by typing gnome-control-center at the command line.

Paste text into any text area
First, highlight the text you want to paste. Then, middle-click (if you have only two mouse buttons, use both at once to emulate the middle button) in the area where you want the text to go. The panel

The preset configuration for many systems has a thin panel along the top and bottom of the screen. The top panel has a set of menus along the upper left, and a few buttons and a clock at the right. The bottom panel contains the window list applet, which should feel familiar to users of Microsoft Windows.

To create a new panel, click any blank space in an existing panel, and choose Panel Figure Create New Panel, then select the type of panel you would like. To change a panel's properties, such as its size and color, right-click it and choose Properties (the menu panel at the top of the screen has no available properties; it is preconfigured for one position and size). Experiment with different kinds of panels and with different sizes to see which ones you like best. If you use a smaller screen, like a laptop screen, you will want to choose a smaller panel size than if you have plenty of screen real estate to use.

To add application launcher buttons to your panels, you can drag them from menus, or right-click the panel and choose Panel Figure Add to Panel Figure Launcher. Then, enter the name of the application you want to run, and choose an icon. You may also choose a description of the launcher that will display as a tool tip when you hover the mouse over the icon in your panel. If you want to launch the application from a terminal, check the "Run in Terminal" box.

For more information on the panel, right-click any empty spot in the panel and select Panel Figure Panel Manual.

Panel applets are small applications that run inside the panel. You can add them to the panel from the Add to Panel menu or just run them by clicking Applications Figure Applets. Panel applets come in a bewildering variety of flavors, from games to utilities. Some of the most common are:

CPU Load
A graph that displays the load on your system resources for the past few seconds.

Workspace Switcher
In most installations, this applet will already be running when you log in, and is typically set to four workspaces. Each workspace is the equivalent of a new screenful of desktop space, and you can have as many as you like. The workspace switcher displays all the virtual workspaces you have created, and displays each window on the desktop as a tiny box. You can use the left mouse button to drag a window from one workspace to another. Right-click and select the Properties menu item to change the number or arrangement of workspaces.

Window List
Like the workspace applet, the Window List is included in most default configurations. It displays the windows that you have open so that you can switch easily among them, even when they are minimized. If you have multiple windows for a single application, they will be grouped under a single entry. To turn this feature off, or to set other options for the applet, right-click the Window List and select Properties.

Battery Charge Monitor
The Battery Charge Monitor displays the remaining battery life for laptop systems. Options include display as a chart, as a percentage, or by estimated usage time remaining.

Displays headlines from Slashdot or the GNOME News web site in your panel.

The Eyes applet consists of a pair of eyeballs that follow your mouse around. It may not be useful, but it's certainly amusing. Nautilus: your desktop and file manager

Nautilus is the name of the GNOME desktop and file manager. It controls the display of your background image and the files on your desktop, allows you to interact with files without using a terminal, and keeps track of your trash for you. In other words, it's the GNOME equivalent of Windows Explorer, the Macintosh Finder, and KDE's Konqueror.

TIP: In most cases, Nautilus will be running when you log in. If it isn't (you'll know: your desktop will not have any icons on it), you can start it from a terminal window by typing nautilus. If you decide you don't want to run Nautilus at all, you can remove it from your session with the Session Properties tool in the Control Center.

Like those other applications, Nautilus lets you drag items from one place to another. You can also copy files using Ctrl-C, cut with Ctrl-X, and paste with Ctrl-V.

The quickest way to get started with Nautilus is to double-click the home icon in the upper-left corner of your desktop, labeled as your home. This will open your home directory.

TIP: Normally, the files on your desktop are stored in ~/.gnome-desktop. However, if you prefer to have your home directory be displayed on the desktop, select Preferences, Edit Preferences, and under the Windows and Desktop category check the "Use your home folder as your desktop" checkbox.

Nautilus looks a good deal like a web browser, and in fact it can be used as one. At the top is a toolbar with buttons that you can use to navigate through your directory structure: back, forward, up, refresh, and home. The location bar, like in a web browser, describes the location of the file or directory you're looking at in this window. If your username is jdoe and you click your Home icon, you'll see /home/jdoe in the location bar.

The left side of the Nautilus window appears to be blank. However, if you look on the lower-left side, you'll notice tabs for Notes, Tree, Help, History, and News, as follows:

  • The Notes tool is a virtual pad of paper where you can jot down any quick reminders you like.

  • The Tree displays the directory tree for your system — click one of the triangles next to a directory and it will spin down, showing you the contents. You can use this tool to navigate your directory structure or to move items around quickly.

  • The Help tab offers up an index of several help systems — help pages for GNOME and KDE applications, plus the more traditional man- and Info pages that come with command-line Linux applications.

  • The History tab will help you trace your steps backward. Not sure where you left that file? You can find out here.

  • The News tab displays headlines that it pulls from various web sites. You can choose your news sources and the frequency with which they update in the Preferences dialog box.

Click a tab and it will expand to fill the sidebar.

Nautilus has some additional fun features that you won't find in other applications, as in:

  • Instead of a generic image icon for graphics files, Nautilus uses scaled-down thumbnails of the image itself. This makes it easy to organize directories full of images, such as those pulled from a digital camera.

  • If you hover your mouse over a music file, the file will begin to play.

  • For text files, the plain document icon is decorated by the actual text contents of the file. That way, you can remember how the file starts without having to open it, even if you didn't give it the most descriptive name.

  • You can stretch icons by right-clicking them and choosing Stretch Icon. If you stretch a text icon enough, you can see the entire contents of the file, and use it as a desktop notepad.

  • Drag any image file onto the background of the left-hand sidebar, and the image will be used as the sidebar background for that directory.

  • For most directories, you can choose to view their contents as a list, or as a group of icons. However, some files have a wider range of options. For example, in a directory full of audio files, you can choose View, and then View as Music, and play the sound files in any order — Nautilus even shows you the artist, title, and playtime for individual files. The same is true of HTML files: Nautilus can display them as their source text or as fully rendered web pages.

All in all, Nautilus is a versatile tool that you can learn to use just by poking around a little. For additional help, just choose Help, and then Nautilus User Manual from any Nautilus window.

Library Navigation Links

Copyright © 2003 O'Reilly & Associates. All rights reserved.