Navigation and settings
Let's spend a moment exploring the Linux panels on the desktop and then look at navigation and an example of how you can customize your desktop by switching to left-handed mouse usage.
Panels give you a starting place for interacting with your desktop and provide information about your system. You will usually find one or two panels on your desktop. Typically these will default to being on the top, the bottom, or both the top and bottom edges of the screen. You can move them to the left or right edges if you wish, typically by right clicking and changing the properties.
Different distributions and different desktops often differ in panel layout, so expect differences here. Our Ubuntu GNOME panels are shown in Figure 8. We've shown the ends of the panels for clarity.
Figure 8. GNOME panel features on Ubuntu
- The left part of the top panel provides a launching place for accessing programs, folders (directories), or system settings and information.
- The right part of the top panel provides information such as time and date, along with several quick-access buttons for functions like setting volume control, opening chat windows, and logging out.
- The left part of the bottom panel has a button to hide all windows and show the desktop, along with buttons for active windows.
- The right part of the bottom panel contains a trash bin and four rectangles that allow you to navigate between your virtual desktops. Most Linux systems set up multiple distinct desktops, so you can keep your email and web browsing on one desktop, while doing program development on another and testing on yet another, for example. You switch between them by clicking the appropriate smaller square or by using a key combination. For GNOME, Ctrl-Alt-left arrow or Ctrl-Alt-right arrow usually cycles through them in the same way that Alt-tab will cycle through application windows on a given desktop. For OpenSUSE, ctrl-F1 through ctrl-F4 will directly select desktops 1 through 4. When exploring, make sure you log in as a non-root user to avoid accidents; such mistakes may be more serious when you have unlimited authority.
The panels for our Fedora system are shown in Figure 9. The System item in the upper left is selected as we used the image from Figure 6 to create this image. Notice that we do not have quick access to the logout function in the upper right, the hide all windows function in the lower left, or the trash icon that we saw in the lower right of the Ubuntu panels. Otherwise, the panel layout is reasonably similar.
Figure 9. GNOME panel features on Fedora
The OpenSUSE system has a panel across the bottom only, as shown in Figure 10. Access to programs as well as folders and system functions starts with the large button at the far left, which we will refer to as the Start button. Also on the left are quick-access buttons to a browser and desktop navigator, followed by buttons for each of the five virtual desktops. On the right end of the panel, you find a clock and several convenience buttons similar to those at the right end of the upper Ubuntu GNOME panel.
Figure 10. KDE 4 panel features on OpenSUSE
The GNOME 2.3x desktop uses the cascading menus that have now become familiar. Figure 11 illustrates how to access the mouse settings from the Fedora System icon. Different distributions may arrange these menus differently. For example, you will find the mouse settings on Ubuntu in the same location, but if you are looking for the Desktop Effects preferences, which you find under System->Preferences->Desktop Effects on our Fedora system, you find it as the Visual Effects tab under System->Preferences->Appearance. Exploring graphical applications is often like turning over different rocks to see what is hiding underneath them.
Figure 11. Accessing mouse settings in Fedora
In contrast, the KDE 4 desktop uses a different metaphor for the Start menu. Menu panels replace each other, and you navigate by clicking on items in the menu or by mousing over the icons at the bottom of the menu. Figure 12 illustrates the Favorites and Applications menus.
Figure 12. Changing KDE 4 menus by mousing over icons
When submenus are selected, such as from Start->Applications->Utilities, a back button opens along the left of the menu so you can return to the previous menu level. Figure 12 illustrates this.
Figure 13. KDE 4 menu back button
Some Start menu items on OpenSUSE open a dialog box, possibly containing further selections. An example is the Start->Applications->Configure Desktop menu, which opens a window like that in Figure 14, where we show the hover help for the Keyboard & Mouse settings menu item.
Figure 14. KDE 4 Configure Desktop menu
A right-handed user is generally assumed, but you can change your mouse configuration for left-handed use, along with many other desktop settings. Refer back to Figure 11 or Figure 14 to navigate to the mouse settings dialog.
On an Ubuntu system, you should see a window similar to Figure 15 where you can change your mouse settings. In addition to basic left-handed or right-handed use, there are several other settings you can change and a tab of additional settings for accessibility. Settings take effect immediately, so once you click the left-handed choice, your mouse is set for left-handed use and you'll have to use the right mouse button as button 1 to close the dialog. The dialog on a Fedora system is similar.
Figure 15. GNOME dialog to change mouse settings
On an OpenSUSE system with KDE, you should see a window similar to Figure 16 where you can change your mouse settings. Note the mouse image in the dialog. If you switch to left-handed use, the right button in the mouse illustration will be highlighted to indicate that it is your primary selection button. Switch back to right-handed use, and the left button will be highlighted. As with the Ubuntu dialog, there are several other options that you can set. Unlike the Ubuntu dialog, the changes only take effect when you click the Apply button.
Figure 16. KDE dialog to change mouse settings