Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyFluency with Information TechnologyThird Editionby Lawrence SnyderChapter 2: What the Digerati Know: Exploring the Human-Computer Interface2-21-2Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyLearning About Technology• People do not have any innate technological abilities– Our experience using (related) devices, including software, shows us what to expect– Designers who create devices, including software, know about this experience and design products to match what we already know2-31-3Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyThe Desktop• Image displayed on the monitor when a PC starts up– Colored or patterned background– Information displayed on top, bottom, or side– Three types of icons:• Applications (programs)• Folders (directories)• Files (documents)2-41-4Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyThe Desktop (cont'd)• "Desktop" is a metaphor– An analogy for computation• Working at PC is analogous to working at a desk– Work goes in files– Files go in folders– Tools (a program or a calculator) are used to perform tasks2-51-5Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyPlaying Recorded Music• Example of metaphoric user interface– Software that plays CDs on computer has Graphical User Interface (GUI)– This GUI resembles a familiar music player• Buttons resemble an ordinary CD player• User can apply knowledge of CD player to learn to use this GUI without special instruction because the metaphor is familiar2-61-6Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley2-71-7Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyUnderstanding the Designer's Intent• Software designers try to pick easy-to-understand user interfaces• We can expect good software to be well crafted so we can "brain out" how it works• We use this idea every time we use new software2-81-8Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyConsistent Interfaces• Designers use metaphors similarly• When we see an icon or metaphor we have seen before, we know how it works• There are standard metaphors found in all GUIs2-91-9Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley2-101-10Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyCommand Buttons• May look like a 3D rectangle or circle, with an icon or text centered on the button• We click mouse to "press" the button and the command is invoked– Tells the software to perform the operation• We receive feedback to confirm the button has been clicked– Color change, shadow, highlight, or audible click2-111-11Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleySlider Control• Sets a value from a "continuous" range, like volume• Move slider by placing mouse pointer on it and dragging in the direction of change– Scroll bars are a type of slider control2-121-12Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyTriangle Pointers• Indicates presence of hidden or alternative information• Clicking on triangle reveals the information– Triangles at the ends of slide bars shift the contents of the window• Experienced users look for familiar metaphors and learn new ones when they are encountered2-131-13Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyAnatomy of an Interface• Menu– List of operations the software can perform– Grouped by similarity of operations– Listed in menu bar– All operations performed by the software are listed in the menu2-141-14Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley2-151-15Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley2-161-16Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyMenu Operation• Menus on the top bar are called pull-down or drop-downmenus– Mouse click reveals list of operations– Sliding mouse down the list highlights items– Clicking or releasing button on highlighted item causes computerto perform that operation• Same operation may be available by icon on a toolbarbelow the menu• Menus that display on a (right) mouse click are called pop-up menus2-171-17Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyReading a Menu• Menus provide information about:– List of items– Submenus– Whether an operation is available– Where more user input is needed– Shortcuts2-181-18Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleySubmenus• Menu items that have a category of choices have a triangle pointer at right end– Example in the Edit menu: Clear• Selecting that item brings up another menu (submenu) with additional choices for that main item2-191-19Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyWhich Operations Are Available?• GUI menu is created each time it is opened• Specify which operations are available in a situation– e.g., copy is not available if nothing is selected to be copied• Unavailable operations are shown in lighter color or "grayed out" and can't be selected– Example in the Edit menu: Cut2-201-20Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyIs More Input Needed?• Items that need more specification have an ellipsis at right end (…)– Example in the Edit menu: Paste Special…• Selecting item pops up an additional menu requiring more input• Software continues to ask for information by opening new windows until it has enough • Then performs operation immediately and closes menu(s) and window(s)2-211-21Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-WesleyIs There a Shortcut?• Menu items may have keyboard shortcuts– Combination of keyboard characters that have the same effect as clicking menu item– Shortcut appears next to menu item– Shortcut consists of combination of special key (meta key) and a letter• For Mac: special key is Command (clover)• For Windows: special key is Control– Shortcuts are usually consistent across operating systems2-221-22Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley2-231-23Copyright ©