5.7 桌面環境

5.7.1.1 關於 GNOME

GNOME is a user-friendly desktop environment that enables users to easily use and configure their computers. GNOME includes a panel (for starting applications and displaying status), a desktop (where data and applications can be placed), a set of standard desktop tools and applications, and a set of conventions that make it easy for applications to cooperate and be consistent with each other. Users of other operating systems or environments should feel right at home using the powerful graphics-driven environment that GNOME provides. More information regarding GNOME on FreeBSD can be found on the FreeBSD GNOME Project's web site. The web site also contains fairly comprehensive FAQs about installing, configuring, and managing GNOME.

5.7.1.2 Installing GNOME

可透過 package 或 Ports Collection 的方式來輕鬆安裝：

透過網路利用 package 安裝 GNOME：

# pkg_add -r gnome2

從 ports tree 透過原始碼編譯安裝 GNOME：

# cd /usr/ports/x11/gnome2
# make install clean

當 GNOME 安裝完成後， 必須告訴 X server 啟動 GNOME 而非原本的 window manager。

啟動 GNOME 最簡單的方法是利 用 GDM(GNOME Display Manager)。 GDM, which is installed as a part of the GNOME desktop (but is disabled by default), can be enabled by adding gdm_enable="YES" to /etc/rc.conf. Once you have rebooted, GNOME will start automatically once you log in —— no further configuration is necessary.

GNOME may also be started from the command-line by properly configuring a file named .xinitrc. If a custom .xinitrc is already in place, simply replace the line that starts the current window manager with one that starts /usr/local/bin/gnome-session instead. If nothing special has been done to the configuration file, then it is enough simply to type:

% echo "/usr/local/bin/gnome-session" > ~/.xinitrc

Next, type startx, and the GNOME desktop environment will be started.

% echo "#!/bin/sh" > ~/.xsession
% echo "/usr/local/bin/gnome-session" >> ~/.xsession
% chmod +x ~/.xsession

Yet another option is to configure the display manager to allow choosing the window manager at login time; the section on KDE details explains how to do this for kdm, the display manager of KDE.

5.7.1.3 Anti-aliased Fonts with GNOME

X11 supports anti-aliasing via its “RENDER” extension. GTK+ 2.0 and greater (the toolkit used by GNOME) can make use of this functionality. Configuring anti-aliasing is described in Section 5.5.3. So, with up-to-date software, anti-aliasing is possible within the GNOME desktop. Just go to Applications->Desktop Preferences->Font, and select either Best shapes, Best contrast, or Subpixel smoothing (LCDs). For a GTK+ application that is not part of the GNOME desktop, set the environment variable GDK_USE_XFT to 1 before launching the program.

5.7.2.1 About KDE

KDE is an easy to use contemporary desktop environment. Some of the things that KDE brings to the user are:

• A beautiful contemporary desktop

• A desktop exhibiting complete network transparency

• An integrated help system allowing for convenient, consistent access to help on the use of the KDE desktop and its applications

• Consistent look and feel of all KDE applications

• Standardized menu and toolbars, keybindings, color-schemes, etc.

• Internationalization: KDE is available in more than 40 languages

• Centralized, consistent, dialog-driven desktop configuration

• A great number of useful KDE applications

KDE comes with a web browser called Konqueror, which is a solid competitor to other existing web browsers on UNIX® systems. More information on KDE can be found on the KDE website. For FreeBSD specific information and resources on KDE, consult the KDE on FreeBSD team's website.

5.7.2.2 安裝 KDE

如同 GNOME 或其他桌面管理軟體一樣， 也可以輕鬆透過 package 或 Ports Collection 來安裝：

To install the KDE package from the network, simply type:

# pkg_add -r kde

pkg_add(1) will automatically fetch the latest version of the application.

To build KDE from source, use the ports tree:

# cd /usr/ports/x11/kde3
# make install clean

After KDE has been installed, the X server must be told to launch this application instead of the default window manager. This is accomplished by editing the .xinitrc file:

% echo "exec startkde" > ~/.xinitrc

Now, whenever the X Window System is invoked with startx, KDE will be the desktop.

If a display manager such as XDM is being used, the configuration is slightly different. Edit the .xsession file instead. Instructions for kdm are described later in this chapter.

5.7.3.1 The KDE Display Manager

An administrator of a multi-user system may wish to have a graphical login screen to welcome users. XDM can be used, as described earlier. However, KDE includes an alternative, kdm, which is designed to look more attractive and include more login-time options. In particular, users can easily choose (via a menu) which desktop environment (KDE, GNOME, or something else) to run after logging on.

To enable kdm, the ttyv8 entry in /etc/ttys has to be adapted. The line should look as follows:

ttyv8 "/usr/local/bin/kdm -nodaemon" xterm on secure

5.7.4.1 About XFce

XFce is a desktop environment based on the GTK+ toolkit used by GNOME, but is much more lightweight and meant for those who want a simple, efficient desktop which is nevertheless easy to use and configure. Visually, it looks very much like CDE, found on commercial UNIX systems. Some of XFce's features are:

• A simple, easy-to-handle desktop

• Fully configurable via mouse, with drag and drop, etc.

• Main panel similar to CDE, with menus, applets and applications launchers

• Integrated window manager, file manager, sound manager, GNOME compliance module, and more

• Themeable (since it uses GTK+)

• Fast, light and efficient: ideal for older/slower machines or machines with memory limitations

More information on XFce can be found on the XFce website.

5.7.4.2 Installing XFce

A binary package for XFce exists (at the time of writing). To install, simply type:

# pkg_add -r xfce4

Alternatively, to build from source, use the ports collection:

# cd /usr/ports/x11-wm/xfce4
# make install clean

Now, tell the X server to launch XFce the next time X is started. Simply type this:

% echo "/usr/local/bin/startxfce4" > ~/.xinitrc

The next time X is started, XFce will be the desktop. As before, if a display manager like XDM is being used, create an .xsession, as described in the section on GNOME, but with the /usr/local/bin/startxfce4 command; or, configure the display manager to allow choosing a desktop at login time, as explained in the section on kdm.