1. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 1 Software Engineering: A Practitioner’s Approach, 6/e Chapter 12 User Interface Design Software Engineering: A Practitioner’s Approach, 6/e Chapter 12 User Interface Design copyright © 1996, 2001, 2005 R.S. Pressman & Associates, Inc. For University Use Only May be reproduced ONLY for student use at the university level when used in conjunction with Software Engineering: A Practitioner's Approach. Any other reproduction or use is expressly prohibited.

2. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 2 Interface Design Interfaces between software modules Interfaces between software modules Interfaces between software and non-human producers and consumers (i.e. Other external entities) Interfaces between software and non-human producers and consumers (i.e. Other external entities) Interfaces between the human (i.e. User) and computer Interfaces between the human (i.e. User) and computer

3. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 3 Interface Design Easy to use? Easy to understand? Easy to learn?

4. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 4 Interface Design lack of consistency too much memorization no guidance / help no context sensitivity poor response Arcane/unfriendly Typical Design Errors

5. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 5 Golden Rules Place the user in control Place the user in control Reduce the user’s memory load Reduce the user’s memory load Make the interface consistent Make the interface consistent

6. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 6 Place the User in Control Define interaction modes in a way that does not force a user into unnecessary or undesired actions. Provide for flexible interaction. Allow user interaction to be interruptible and undoable. Streamline interaction as skill levels advance and allow the interaction to be customized. Hide technical internals from the casual user. Design for direct interaction with objects that appear on the screen.

7. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 7 Reduce the User’s Memory Load Reduce demand on short-term memory. Establish meaningful defaults. Define shortcuts that are intuitive. The visual layout of the interface should be based on a real world metaphor. Disclose information in a progressive fashion.

8. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 8 Make the Interface Consistent Allow the user to put the current task into a meaningful context. Maintain consistency across a family of applications. If past interactive models have created user expectations, do not make changes unless there is a compelling reason to do so.

9. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 9 User Interface Design Models User model — a profile of all end users of the system categorization as novice, intermittent, or frequent user & expert User model — a profile of all end users of the system categorization as novice, intermittent, or frequent user & expert Design model — data, architectural, interface, and procedural representations Design model — data, architectural, interface, and procedural representations Mental model (system perception) — the user’s mental image of what the interface is Mental model (system perception) — the user’s mental image of what the interface is Implementation model — the interface “look and feel” coupled with supporting information that describe interface syntax and semantics Implementation model — the interface “look and feel” coupled with supporting information that describe interface syntax and semantics

10. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 10 User Interface Design Process

11. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 11 User Interface Design Process  The initial analyis activity focuses on the profile of the users who will interact with the system. For each class of users, requirements are elicited.  Once the general requirements have been defined, a more detailed task analysis is conducted.  Analysis of the user environment focuses on the physical work environment.

12. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 12 User Interface Design Process  Interface design defines a set of interface objects and actions (& their screen representations) that enable a user to perform all defined tasks.  Implementation activity normally begins with the creation of a prototype that enable user scenarios to be evaluated.  Validation focuses on * the ability of the interface to implement every tasks correctly and to achieve all user requirements. * the ability of the interface to implement every tasks correctly and to achieve all user requirements. * the degree to which interface is easy to learn and use. * the users´ acceptance of the interface as a useful tool in their work.

13. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 13 Task Analysis and Modeling Answers the following questions … Answers the following questions … What work will the user perform in specific circumstances? What work will the user perform in specific circumstances? What tasks and subtasks will be performed as the user does the work? What tasks and subtasks will be performed as the user does the work? What specific problem domain objects will the user manipulate as work is performed? What specific problem domain objects will the user manipulate as work is performed? What is the sequence of work tasks—the workflow? What is the sequence of work tasks—the workflow? What is the hierarchy of tasks? What is the hierarchy of tasks? Use-cases define basic interaction Use-cases define basic interaction Task elaboration refines interactive tasks Task elaboration refines interactive tasks Object elaboration identifies interface objects (classes) Object elaboration identifies interface objects (classes) Workflow analysis defines how a work process is completed when several people (and roles) are involved Workflow analysis defines how a work process is completed when several people (and roles) are involved

14. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 14 Swimlane Diagram

15. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 15 Interface Design Steps Using information developed during interface analysis (SEPA, Section 12.3), define interface objects and actions (operations). Using information developed during interface analysis (SEPA, Section 12.3), define interface objects and actions (operations). Define events (user actions) that will cause the state of the user interface to change. Model this behavior. Define events (user actions) that will cause the state of the user interface to change. Model this behavior. Depict each interface state as it will actually look to the end-user. Depict each interface state as it will actually look to the end-user. Indicate how the user interprets the state of the system from information provided through the interface. Indicate how the user interprets the state of the system from information provided through the interface.

16. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 16 Interface Design Patterns Patterns are available for Patterns are available for The complete UI The complete UI Page layout Page layout Forms and input Forms and input Tables Tables Direct data manipulation Direct data manipulation Navigation Navigation Searching Searching Page elements Page elements e-Commerce e-Commerce

17. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 17 Design Issues Response time (length & variability) Response time (length & variability) Help facilities (integrated or add-on) Help facilities (integrated or add-on) Error handling Error handling Menu and command labeling Menu and command labeling Application accessibility Application accessibility Internationalization Internationalization

18. These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach, 6/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001, 2005 18 Design Evaluation Cycle