Lesson 12-Accessing and Exploring Graphical Desktops

1. Lesson 12-Accessing and Exploring Graphical Desktops

2. Overview • The UNIX/Linux graphical desktop. • Starting the X Window system from a terminal. • Exploring the graphical desktop environment.

3. The UNIX/Linux Graphical Desktop • UNIX and Linux support both graphical and character-based terminals. • GNOME (GNU Network Object Model Environment) and KDE (K Desktop Environment) are the two most popular flavors of the graphical desktop. • The X Window system is the fundamental graphical tool that enables particular desktop window managers such as GNOME and KDE to operate.

4. Starting the X Window System from a Terminal Launching X Window system from Linux: • The “startx” command starts the fundamental graphics program, the X Window system, and then launches your account’s default window manager. • A desktop with icons, menu bar, and an active mouse is displayed. • The startx utility flags an error if X Windows is not properly installed.

5. Starting the X Window System from a Terminal Launching X Window system from UNIX: • In UNIX environment, the “xinit &” command starts the fundamental graphics program, the X Window system. • A full graphical desktop environment is displayed once the X Window session is started.

6. Starting the X Window System from a Terminal Launching X Window system from UNIX (continued): • The "gnome &" or the "kde &" command can be used for selecting a particular graphical interface or desktop. • The Motif Window Manger ("mwm &") or the blackbox "blackbox &" desktop program can also be started.

7. Exploring the Graphical Desktop Environment A generic GNOME desktop

8. Exploring the Graphical Desktop Environment • Navigating the Task Bar. • Accessing applications through the Main Menu. • Moving, resizing, and iconifying Windows. • Starting programs with icons.

9. Exploring the Graphical Desktop Environment • Using the menu bar. • Customizing the desktop environment. • Exiting a session from the desktop.

10. Navigating the Task Bar • The Task Bar, by default, appears at the bottom of the desktop. • In the GNOME and KDE interface, various icons on the desktop allow a user to access the Terminal Emulator, Help, web browser, and other features. • The Task Bar contains a wide variety of configurable settings and features.

11. Navigating the Task Bar • The Terminal Emulator or the Console icon opens a terminal window where shell commands can be executed. • Multiple terminal windows can be created on the screen to work in two or more environments at the same time. • A terminal window uses a default font unless the –fn option has been specified.

12. Navigating the Task Bar • The r16 and r24 font can be used for configuring the font size. • The Task Bar also contains a set of four clustered buttons that allows a user to switch to an alternate desktop.

13. Accessing Applications through the Main Menu • The Main Menu in GNOME or the Start Application in KDE pops up a menu that provides access to various programs, utilities, settings, and other system menus. • The Main Menu provides access to various programs and utilities for working, like spreadsheets, address book, word processor, calculator programs, games, etc.

14. Moving, Resizing, and Iconifying Windows • The window manager interprets mouse clicks and drags in the usual ways. • The handle on the sidebar of the window allows the window to be reshaped. • The minimize button is located at the top-right corner of the window, and is represented in the form of an underscore.

15. Moving, Resizing, and Iconifying Windows • The icon of the active window is placed at the center of the Task Bar. • A Help or Documentation browser is an interface to the various forms of documentation on the computer as well as the Internet. • A web browser such as Netscape, Mozilla, or Galeon is usually included with X Windows and can be accessed either through the Task Bar or the Main Menu.

16. Starting Programs With Icons • The icons on the desktop can be customized or removed according to the user’s preferences. • The Trash icon in the desktop is similar to a Recycle bin and can be used for recovering documents that get accidentally deleted. • The “Empty Trash” option deletes the files permanently from the system.

17. Using the Menu Bar • The menu bar has functions like a quick reference location for frequently used applications, configurations, and even favorite web sites. • Application, Utilities, Development, and Games are some of the topics that appear in the drop-down menu when the Programs icon on the Task Bar is clicked. • A web page saved as favorites in the browser also appears for quick reference.

18. Customizing the Desktop Environment • The appearance of the desktop can be easily changed with the help of the pop-up menu that appears when the mouse is right-clicked on the desktop. • The screen saver and various other options can be configured with the help of the Main Menu. • X Windows also allows shortcuts to be created on the desktop for frequently used programs with a simple drag-and-drop operation.

19. Exiting a Session From the Desktop • A desktop session in GNOME can be exited by using the Main Menu, while in KDE, the Start Application is used to achieve the same. • The “Lock Screen” option keeps the current session alive, but requires the user to provide a password to unlock the screen.

20. Exiting a Session From the Desktop • The “Logout” option can be selected either from the pop-up menu that appears when the desktop is right-clicked, or from the Main Menu.

21. Summary • In UNIX and Linux, the X Window system provides users with a full graphical environment. • Login accounts can be configured to start up in the graphical or terminal mode. • In the graphical desktop, the dashboard, or Task Bar, provides a series of menus and icons for easy access to programs.