Slides for User interface design A software engineering perspective Soren Lauesen 9. Reflections on user interface design August 2006 © 2005, Pearson Education retains the copyright to the slides, but allows restricted copying for teaching purposes only. It is a condition that the source and copyright notice is preserved on all the material.

Fig 9.1 The Virtual Window method Test Virtual window design Program Domain analysis Function design Prototype + usability test Interview Observation Doc study Usability factors Mental models Presentation forms Gestalt laws Understandability test CREDO etc. Task needs Semantic functions State diagrams Function presentation Combine details Heuristic evaluation Usability test Revise - iterate One more usability test Task descriptions Data model Usability requirements Function list Screen plan Mini-specs Virtual windows Revised tasks and data model Proven prototype Defect list Program text

3. Virtual Window method - overview Data modelTask descriptions Virtual windows Mockup Functions visualized Open, Close Goto, Back Navigation functions for a real screen Programming Usability testing Understand- ability testing Search, New Check in, Print Functions needed on a giant screen

Fig 9.2A Data and functions: Virtual Window method Time Data System functions User actions Task descriptions Usability requirements Semantic functions Use cases Data model Virtual windows Prototype Visible to user Visible to user Page plan Usability testing Function presentation Navigation functions

Fig 9.2B Data and functions: Sutcliffe (1988) Data model Time Data System functions User actions Presentation design Modules Task analysis User description Task design Interaction style Work units Dialogue design Visible to user

Fig 9.2C Data and functions: OO methods Static model Time Data System functions User actions Analysis model Use cases Screen objects (prototype) Visible to user Design model ?? Responsibilities

Checkin Fig 9.3 Old version of function design NewStay period, type … FindStay FindRoom PrintConfirm Book Stay Rooms name, addr …