Collins presents a principled approach to designing user interfaces for systems built on modern hardware and software platforms. In the text, Collins defines object-oriented user interface, presents a methodology for designing both the visible features of the interface and the software structures underlying it, and demonstrates how this methodology fits into the context of object-oriented development. Collins provides the reader with a single conceptual model, grounded in standard engineering practice, to guide both external and internal design of the user interface. The author's methodology, based on object-oriented principles, is consistent with other object-oriented methodologies for system and database design.
- Delivers a clear definition of "object-oriented" user interface consistent with other OO paradigms and contexts
- Draws on many diverse fields such as software engineering, cognitive psychology, human factors, and graphic design
- Covers the design of the visible interface and the software that implements it
- Describes object-oriented implementation architectures which flow naturally from the user interface
- Provides examples in C++ and Smalltalk to illustrate the implementation of object-oriented user interfaces
The User Interface.
Plan of the Book.
Audiences for the Book.
Relation to Other Design Approaches.
I. FOUNDATIONS.2. A Bit of History.
People, Work or Technological Change.
Knowledge Workers and Production Workers.
Evolution of the User Interface.
User Interface Technology - Yesterday, Today, Tomorrow.3. Two User Interface Styles.
Analyzing User Interfaces.
Discussion.4. Applying Object-Orientation To User Interfaces.
A Model of Object-Orientation.
Cognitive Models for Object-Orientation.
Object Orientation in User Interfaces.5. Three Domains of Oo Design For The User Interface.
Designing for Understandability.
The Three Domains.
An Example: "Klondike" Solitaire.6. Ooui Design: Process and Team.
Models of the Development Process.
The OOUI Design Process.
Skills Required for OOUI Design.
Role of the UI Design Team in Development.
Managing the OOUI Design Process.
II. EXTERNAL DESIGN.7. Users, Tasks, and Task Analysis.
Why Task Analysis?
Users and Their Tasks.
Task Analysis and Task Synthesis.
Documenting Task Analysis.
Tasks as Objects.8. The User's Conceptual Model.
Models and Metaphors.
Users' Models of Systems.
Designing the User's Conceptual Model.
A Catalog of Metaphors.9. Information Presentation.
Human Senses, Information, and Technology.
Views, Presentation Metaphors, and Patterns.
Step-by-Step Presentation Design.
Content View Design.
Differences Between Computers and Other Media.10. Interaction and Control.
Step-by-Step Interaction Design.
Documenting Look and Feel.
III. INTERNAL DESIGN AND IMPLEMENTATION.11. Object-Oriented System Architectures.
An OO View of Systems and Applications.
The Model-View-Controller Architecture.
An Architecture for Object-Oriented Client-Server.
Applications.12. Information Models.
"Middle Out" User Interface Design.
Modular Separation of Information Models and Interaction.
A "Three-Schema" Approach to User Interfaces.13. Presentation and Interaction Objects.
Views and Interactors.
Design and Code Reuse.
Direct Manipulation Interaction.
Object Handlers.14. Tools For Prototyping and Implementation.
Visual Interface Builders.
Portability.15. Putting it All Together.
The Whole Interface.
Case Study: Online News Photos, With and Without Seams.
Case Study: A Distributed Multimedia System.
Case Study: Adding Fax to an Office System.
Pragmatic issues of OOUI Implementation.16. Summary and Directions.
Key Points of the Book.
The Future of the OOUI.
Where to Go From Here.Appendix 1. Fax Case Study.
Designing Object-Oriented User Interfaces presents a principled approach to developing user interfaces for modern hardware and software platforms. It defines what an object-oriented user interface is, and provides a methodology for designing the visible interface and its underlying software. The principles and practices presented here are based on development experience and academic research. The book is intended for both working developers and for students and teachers in academic and industrial settings.
Object-orientation reflects the way people --including end users and system developers-- perceive, think, and act. The foundation for this book is the idea that the same set of object-oriented principles can be applied to end user interfaces and to the internal system structures that implement them. This results in a user interface design methodology that fits seamlessly into object-oriented design and development processes for entire systems.
Design, if it is meaningful, occurs in the context of development (even for students, exercises must assess how the design will function when it is built). To get the most out of this book, it is important to go beyond it and do real designs. Start with tasks that people do, sketch designs for interfaces, implement the sketches, and show the results to potential users. Designers are often surprised by how hard it is to implement simple ideas, and by the way users respond to them. This surprise factor never goes away; becoming comfortable with it is a sign of maturity as a user interface designer.
The same thing goes for this book, I have tested the principles and practices in my own projects and by analyzing their use in other projects large and small. Nevertheless, I am sure there are still surprises in store, and lessons to be learned, I invite your comments and suggestions about any aspect of the book, particularly its applicability to development projects you are involved in. Comments can be sent by electronic mail to firstname.lastname@example.org, or by post to P.O. Box 24, Pleasantville, NY 10570, USA.
Though I was not aware of it at the time, the motivation for this book probably came in 1984 when I first saw an Apple Macintosh computer. I was already a user of graphics systems, but the idea of a computer on which everything was done by manipulating visible images was novel, and profoundly appealing.
Conscious work started in early 1988, when my colleague, Chamond Liu, was putting together a conference on object-oriented systems (held at the IBM Education Center at Thornwood, New York). I was interested both in object-oriented programming languages and in the usability of human-computer interfaces, and Chamond asked me to chair a session on object-oriented user interfaces. He also asked me to make a presentation dealing with the connection (or lack of connection) between the principles of objects, classes, and inheritance as applied to programming languages, and analogous principles applied to the external behavior of user interfaces.
Chamond's request started me on a long journey. As I digested literature from areas as diverse as computer architecture and cognitive psychology, connections became apparent not only between user interfaces and programming, but between systems and methods used to develop them. These connections were manifest in the construction of many significant object-oriented systems, as described by the people who had designed and built them. Since then, my understanding of the connections has been deepened by experience as both developer and user of systems with object-oriented user interfaces.
Starting with my talk at the conference in November of 1988, discussion and presentation of the ideas went on through many tutorials and short courses on aspects of object-oriented user interfaces. Talking with designers and implementors who attended these helped to confirm the basic ideas, and expanded my understanding in areas where I lacked personal experience.
There is now a large body of ideas and methods for object-oriented user interface design. I think it is fair to say that a consensus exists on at least the broad outline of a methodology. By 1992 I felt that making these ideas and methods available within a coherent development framework would advance the practice of design, and the result is this book.
This book was produced in camera-ready form from a manuscript written in Microsoft Word and FrameMaker, running on Microsoft Windows. It is set in fonts from the TrueType Lucida family. Screen images and halftone art were processed with ImagePals, from Ulead Systems. Line art was prepared with CorelDraw, from Corel. Application examples done specifically for the book were coded with Smalltalk/V from Digitalk, ParcPlace Smalltalk, and Borland C++.
The availability of tools allowing an author to produce a book, with all its text and artwork, is a remarkable example of what computers can do, and part of a revolution as profound as what followed the invention of moveable type in the 16th century. I thank the developers of the products that allowed me to accomplish this feat, and encourage them to make it easier in the future.
A book as broad as this synthesizes the work of many people. Ideas have come from published papers, presentations, conversations, and user interface implementations in products and research prototypes. Specific ideas that I have used are acknowledged in the text. In addition, many people have contributed to my general understanding of the field and opened my eyes to possibilities for user interface designs. Though I take full responsibility for any deficiencies in this book, its value could not have been achieved without those people.
The first twenty years of my career in the computer industry were spent in daily contact with customers and end users of computers. I owe my first debt to them, for teaching me things about the experience of human-computer interaction that I could not have learned in any other way.
I have given courses and tutorials based on this material to people from many disciplines and with varying amounts of background knowledge. I thank all the students in those courses for their patience and their feedback. Students pointing out problems based on their experiences led to many improvements in the ideas and methods.
Developing a curriculum in software usability for IBM over the period 1988-1992 provided the opportunity to hear ideas from leading people in the field of user interface design. Contact with people like Bill Buxton, Charles Irby, Ted Nelson, Ben Shneiderman, Edward Tufte, and many others was both educational and inspiring. I am grateful for the support of the human factors community within IBM during that same period. People too numerous to mention gave up their time to help me understand how human factors could be applied in development. Walter Baker, John Bennett, John Gould, Dick Granda, Richard Halstead-Nussloch, and Ron Shapiro were particularly generous. The information development and graphic design communities in IBM also helped me to understand the role of those disciplines in user interface design and development.
Managers and colleagues at the IBM Systems Research Education Center and at the User Interface Institute of IBM Research were consistently helpful and supportive. Chamond Liu, as mentioned above, provided the key idea that got me started. Bob Mack encouraged both the book and the research behind many of the ideas about implementation. Many others provided helpful ideas and encouragement.
Thanks to Dan Joraanstad, of Benjamin Cummings, and Grady Booch, series editor for the Object-Oriented Software Engineering series, for encouraging the book at its inception. Thanks also to Tim Cox, Ari Davidow, Ray Kanarr, Laura Cheu, Melissa Standen, Lisa Jahred, and others at Benjamin/Cummings for keeping it on track as we went along.
The following people provided concrete help while the book was being written, in the form of discussions or reviews of chapter drafts: Walter Baker, Steve Berczuk, Katherine Betz, Grady Booch, Steve Goetze, Reza Jalili, Chamond Liu, Bob Mack, Linn Marks, Brad A. Myers, Steve Otto, Jim Poretta, James Purtilo, Mary Beth Rosson, Kenneth S. Rubin, Drasko Sotirovski, George Vanecek, Mark Wilkes, and Kirk Wolf. Their feedback improved both the content and style of the book.
Thanks most of all to Linn Marks. She has given me a steady stream of visual design ideas for user interfaces and for the book itself. Many ideas here were generated or sharpened in the course of long discussions on the art and science of design. She also provided the constant encouragement I needed to persevere through the period of more than a year, while I struggled to get these ideas down on paper in the form in which you now see them.