GRAPHICAL USER INTERFACE Computer Systems Concepts Presentation on GRAPHICAL USER INTERFACE Presented By- Said Mohammad Al-rashdi April 2012 Submitted to- Dr. Tariq Gasemi Information Systems Section College of Economics Management and Information Systems

Overview GUI concept History of GUI Examples GUI Features & Tasks User Interface Design Process Comparison between CLI & GUI

GRAPHICAL USER INTERFACE A graphical User Interface (GUI), is often pronounced as ‘goo-ey’. It is a type of user interface that controls a display for the user and allows users to interact with programs. A GUI offers graphical icons, and visual indicators. It was developed because interacting with computers in text mode (C.L.I.) was a very time consuming & cumbersome activity.

History The first graphical user interface was designed by Xerox Corporation's in 1970s. But became popular after the Apple Macintosh’s emergence in 1980’s. Before GUI was developed the operating system was strictly text based. The 1st commercial GUI

A GRAPHIC USER INTERFACE (GUI) DESKTOP GRAPHIC ICONS POINTER A GRAPHIC USER INTERFACE (GUI) DESKTOP

GUI examples

Features Pointer : A symbol that appears on the screen and used to select objects and commands. It is a small angled arrow. Text –it is I-beam pointer that is shaped like a capital I. Pointing device : A device, such as a mouse or trackball, that enables you to select objects on the display screen.

Cont… icons : Small pictures that represent commands, files, or windows. By a simple click on it we can execute a command/program or convert the icon into a window desktop : The area on the display screen where icons are grouped. menus : Most graphical user interfaces let you execute commands by selecting a choice/option from a menu.

Common GUI tasks Titles / Text Fields / Dialog boxes Buttons Names Prompts User instructions Fields / Dialog boxes Input Output Buttons Let the user initiate actions Let the user select among a set of alternatives e.g. yes/no, blue/green/red, etc.

Common GUI tasks (cont.) Display results Shapes Text and numbers Make a window “look right” Style and color Note: our windows look different (and appropriate) on different systems More advanced Tracking the mouse Dragging and dropping Free-hand drawing

GUI From a programming point of view GUI is based on two techniques Object-oriented programming For organizing program parts with common interfaces and common actions Events For connecting an event (like a mouse click) with a program action

Command Line Interface

Command interfaces * User types commands to give instructions to the system e.g. UNIX * May be implemented using cheap terminals. * Easy to process using compiler techniques * Commands of arbitrary complexity can be created by command combination * Concise interfaces requiring minimal typing can be created.

Problems with command interfaces: * Users have to learn and remember a command language. * Users make errors in command. An error detection and recovery system is required * System interaction is through a keyboard so typing ability is required

Comparison between CLI & GUI- GUI- much easier to learn & use than CLI (Command-Line Interface). In CLI the commands are textual,& in GUI commands are graphical. GUI provides a screen full of graphic icons or menus to users. In GUI a point-&-draw (mouse, joystick etc) device is used. Eg- To delete file in CLI = rm <filename> , & in GUI by click on the item & select delete option.

CLI & GUI Eg- To delete file in CLI = c:\> del <filename> , & in GUI by click on the item & select delete option.

Modify-edit-delete by click CLI & GUI GUI Command easy Difficult Clear Not Any user Prof. user attractive Basic Modify-edit-delete by click Need codes Color Screen Black & White Screen Graphic Text

Summary GUI definition History of GUI Examples of GUI in Software & OS GUI Features & Multi- Tasks User Interface Design Process Comparison between CLI & GUI

Refrences http://www.stroustrup.com http://www.ics.uci.edu/~taylor/ICS_52_FQ02/ICS52FQ02-06.pdf http://www.authorstream.com/Presentation/dhirj4u-540274-presentation-gui/ http://www.ats.ucla.edu/stat/mlwin/faq/command_line.htm

THANK YOU.. Questions.. Discussion..