The User

							Interaction Styles
     Lecture 7
 Date: 23rd February




                       1
          Overview of Lecture

•Interaction style definition

•Major interaction styles
  •Direct manipulation

  •Menu Selections, form fillin & dialog boxes

  •Command Languages




                                                 2
             Interaction Styles




Interaction is the dialogue between the computer
and the user
Interaction styles refer to the ways in which users
communicate or interact with computer systems
                                                      3
            Graphical Screens

•The most common interface that users are exposed
to today is the Graphical User Interface (GUI)

•Graphic presentation utilises the users information
processing capabilities much more effectively than
other presentation methods

•It permits faster transfer of information to the user by
allowing visual comparisons of various information

•It permits more compact representation of
information and simplification of the perception of
structures


                                                            4
           Graphical Screens

•Graphical screens increase the potential for
great visual clutter and user confusion
because of its variety and complexity


•The number of available components in a
graphical environment greatly outnumbers
those of a textual screen




                                                5
                   Graphical Screens
 WIMPs (Windows, Icons, Menu, Pointers) is central to the
 concept of GUIs


Window is a means of sharing a computer’s graphical display
resources among multiple applications simultaneously

Icon is an image or symbol used to represent a file, folder,
application or device

Menu is a list of command/options which the user can choose




Pointer is a pointing device such as a mouse
                                                               6
   Graphical Screens
Elements of the WIMP interface




                                 7
               Interaction Styles




   Direct         Menu Selection    Command
Manipulation        Form Fillin     Languages
                   Dialog Boxes


                                                8
               Interaction Styles




   Direct         Menu Selection    Command
Manipulation        Form Fillin     Languages
                   Dialog Boxes


                                                9
         Direct Manipulation

•A direct manipulation interface is one where
graphical objects on the screen are directly
manipulated with a pointing device.

•User actions involve dragging, selecting,
opening, closing and zooming actions on
virtual actions


•WIMPs is central to the concept of direct
manipulation.

                   Direct Manipulation          10
           Direct Manipulation
Advantages
•Intuitive, easy to learn and remember.

•Reduces errors as minimal syntax required.

•Allows rapid actions, and reversals.

•Enjoyable and encourages exploration by immediate
feedback and evaluation.

•Users experience less anxiety, sense of confidence
and control.


                      Direct Manipulation             11
                Direct Manipulation
Disadvantages
•More difficult to program (especially error handling).
•High resource usage – e.g. memory and CPU
•Requirement for lots of screen space may be
cumbersome e.g. need to scroll.
•Pointing may be slower than typing.
•Visual representation may mislead:
   • Not all objects and tasks can be described visually; and
   • not all actions can be done by direct object manipulation.
•May increase difficulties for visually impaired.



                            Direct Manipulation                   12
          Direct Manipulation
Examples of direct manipulation:
  •Word Processors/Display Editors e.g., Microsoft
  Word

  •Spreadsheets e.g., Microsoft Excel

  •Spatial Data Management e.g., ArcView

  •Video games

  •Computer-Aided Design

  •Office automation e.g., Microsoft Windows

                    Direct Manipulation              13
      Word Processors/Display Editors
•Training times with display editors are much less than line
editors
•Line editors are generally more flexible and powerful
•The advances of WYSIWYG word processors:
   •Display a full page of text
   •Display of the document in the form that it will appear when the final
   printing is done
   •Show cursor action
   •Control cursor motion through physically obvious and intuitively
   natural means
   •Use of labeled icon for actions
   •Display of the results of an action immediately
   •Provide rapid response and display
   •Offer easily reversible actions

                              Direct Manipulation                            14
      Word Processors/Display Editors


Technologies that derive from the word processor:
• Integration
• Desktop publication software
• Slide-presentation software
• Hypermedia environments
• Improved macro facilities
• Spell checker and thesaurus
• Grammar checkers




                       Direct Manipulation          15
Word Processors/Display Editors




           Direct Manipulation    16
                 Spreadsheets


Technologies that derive from the word processor:
• Integration
• Desktop publication software
• Slide-presentation software
• Hypermedia environments
• Improved macro facilities
• Spell checker and thesaurus
• Grammar checkers




                       Direct Manipulation          17
         Spatial Data Management


• In some cases, spatial representations provide a
  better model of reality

• Successful spatial data-management systems
  depend on choosing appropriate:
   • Icons
   • Graphical representations
   • Natural and comprehensible data layouts




                       Direct Manipulation           18
Spatial Data Management




         Direct Manipulation   19
                    Video Games
• From PONG to Nintendo GameCube, Sony PlayStation 2, and
  Microsoft Xbox
• Field of action is visual and compelling
• Commands are physical actions whose results are
  immediately shown on the screen
• No syntax to remember
• Most games continuously display a score
• Direct manipulation in SimCity
• Most well received
• DOOM and Quake controversial


                          Direct Manipulation           20
        Computer Aided Design

Computer-aided design
• Computer-aided design (CAD) use direct
  manipulation
• Manipulate the object of interest
• Generate alternatives easily
• Explain the impact
• Problem solving by analogy to the real-
  world

                  Direct Manipulation       21
Computer Aided Design




        Direct Manipulation   22
            Summary of Lecture
• Interaction styles refer to the ways in which users
  communicate or interact with computer systems

• Direct Manipulation
   •   Word Processors/Display Editors
   •   Spreadsheets
   •   Spatial Data Management
   •   Video games
   •   Computer-Aided Design

• Menu Selection
• Command Languages



                         References                     23
         Terms of Reference
• Shneiderman, B. & Plaisant, C. (2005)
  Designing the User Interface

• Preece, J. et al. (2002) Interaction Design

• Benyon, D. et al (2005) Designing
  Interactive Systems

• Helander, M. et al (1997) Handbook of
  Human-Computer Interaction

• Norman, D. (1990) The Design of Everyday
  Things

                    References                  24