The document discusses the design of user interface (UI) layers, emphasizing the responsibilities of view layer objects in responding to user interactions and displaying business objects. It outlines a four-step design process involving both macro and micro levels, where macro design focuses on identifying and defining interactions through analysis and diagrams, while micro design applies specific rules and guidelines to enhance usability. Key considerations include simplicity in interface design and the impact of additional features on performance and complexity.

1. View layer : Designing interface
objects

2. Introduction
• UI(user interface)
– Main goal of UI is to display and obtain needed
information in an accessible , efficient manner
– UI design is a creative process

3. Designing view layer classes
• UI layer consists of
– objects with which user interacts
– Objects needed to manage or control UI
• Responsibility of view layer objects
– Input :responding to user interaction
• Translating user’s action into an appropriate response
– Output :displaying or printing business objects

4. Process of designing view layer classes
• It has 4 major activities
– Macro level UI design process: (identifying view layer object)
• Takes place during analysis phase
• Identifying classes that interact with human actors by analysing use
cases
• sequence and collaboration diagram helps to identify UI classes
– Micro level UI design activities
• Designing the view layer objects by applying design axioms and
corollaries
– Decide how to use and extend the components so they best support
application specific functions and provide the most usable interface
• Prototyping the view layer interface
– Useful in the early design process
– Testing usability and user satisfaction
– Refining and iterating the design

5. Macro level design process
The class
interacts with a
human actor
Zoom in by utilizing
sequence or collaboration
diagrams
Next class
refine and
iterate
Identify the interface
objects for the class
Define the relationships
among the view objects
The class
doesn’t
interacts with
the human
actor

6. Access objects
Business objects
View objects
Relationship among view objects,
business objects, access objects

7. Micro level design process
Apply micro level UI
design rules and GUI
guidelines to each
interface object identified
to develop the UI
Next interface
objects refine
and iterate
Done

8. Design rules
• Making the interface simple ( application of corollary 2)
– Ex:
• Car engine is complex
• But driver interface remains simple
– User must be able to work with our screen without asking much
questions
– Factors affecting UI
• Dead lines
• Comparative evaluations
• Addition features
• Shortcuts
– Things to be considered while designing UI
• Additional features affect performance, complexity
• Fixing problem, after the release of product is difficult