Transcript Chapter 7 Instructor Slides

Chapter 7
User Interface, Input, and Output
Design
Design Phase Description
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Systems Design is the third of five phases in
the systems development life cycle (SDLC)
Begin the physical design of the IS that meet
the specifications described in the system
requirements document
IS design tasks include data design, user
interface design, and system architecture
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Chapter Objectives
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Explain the concept of user interface design
and human-computer interaction, including the
basic principles of user-centered design
List specific guidelines for user interface
design
Describe user interface techniques, including
screen elements and controls
Explain input design concepts, techniques, and
methods
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Chapter Objectives
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Describe guidelines for data entry screen
design
Use validation checks for reducing input
errors
Design effective source documents and input
controls
Discuss output design issues and various
types of output
Design various types of printed reports, and
suggest output controls and security
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Introduction
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User interface, input, and output design
continues the systems design phase of
the SDLC
User interface design includes user
interaction with the computer, as well
as input and output issues
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Prototyping
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Interactive feedback from stakeholder
using a walk-thru demo to confirm
requirements are being meet
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Storyboard
Static Model
Functional Model
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Total Cost of Ownership
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Cost of building or buying
Cost to replace
Cost to maintain
Cost to operate
Cost to customer good will
Cost to stakeholder satisfaction
Lost opportunity costs
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User Interface Design
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After the logical model is constructed,
systems analysts turn their attention to
the physical design
A key design element is the user
interface (UI)
Consists of all the hardware, software,
screens, menus, functions, and features
that affect two-way communications
between the user and the computer
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User Interface Design
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Human-Computer Interaction
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Human-computer interaction (HCI)
describes the relationship between
computers and people who use them to
perform business-related tasks
IBM uses its Almaden computer science
research site to focus on users and how
they experience technology
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User Interface Design
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Human-Computer Interaction
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IBM traces the history and evolution of the
human-computer interface — beginning with users
typing complex commands in green text on a
black screen, through the introduction of the
graphical user interface (GUI)
Dr. Clare-Marie Karat states that “in this new
computer age, the customer is not only right, the
customer has rights”
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User Interface Design
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Human-Computer Interaction
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The user rights cited by Dr. Karat include
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Perspective
Installation
Compliance
Instruction
Control
Feedback
Dependencies
Scope
Assistance
Usability
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User Interface Design
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Basic Principles of User-Centered
Design
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Understand the underlying business
functions
Maximize graphical effectiveness
Profile the system’s users
Think like a user
Use prototyping
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Usability metrics
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User Interface Design
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Basic Principles of User-Centered
Design
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Design a comprehensive interface
Continue the feedback process
Document the interface design
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User Interface Design
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Guidelines for User Interface Design
Follow eight basic guidelines
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Focus on basic objectives
Build an interface that is easy to learn and
use
Provide features that promote efficiency
Make it easy for users to obtain help or
correct errors
Minimize input data problems
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User Interface Design
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Guidelines for User Interface Design
Follow eight basic guidelines
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Provide feedback to users
Create an attractive layout and design
Use familiar terms and images
Good user interface design is based on a
combination of ergonomics, aesthetics,
and interface technology
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User Interface Design
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Guidelines for User Interface Design
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Focus on basic objectives
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Facilitate the system design objectives
Create a design that is easy to learn and
remember
Design the interface to improve user efficiency
and productivity
Write commands, actions, and system
responses that are consistent and predictable
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User Interface Design
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Guidelines for User Interface Design
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Build an interface that is easy to learn and
use
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Label clearly all controls, buttons, and icons
Select only those images that a user can
understand easily
Provide on-screen instructions that are logical,
concise, and clear
Show all commands in a list of menu items
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User Interface Design
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Guidelines for User Interface Design
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Provide features that promote efficiency
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Organize tasks, commands, and functions in
groups that resemble actual business
operations
Create alphabetical menu lists
Provide shortcuts so experienced users can
avoid multiple menu levels
Use default values if the majority of values in a
field are the same
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User Interface Design
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Guidelines for User Interface Design
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Make it easy for users to obtain help or
correct errors
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Ensure that Help is always available
Provide user-selected Help and contextsensitive Help
Provide a direct route for users to return to the
point from where Help was requested
Include contact information
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User Interface Design
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Guidelines for User Interface Design
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Minimize input data problems
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Provide data validation checks
Display event-driven messages and reminders
Establish a list of predefined values that users
can click to select
Build in rules that enforce data integrity
Use input masks
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User Interface Design
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Guidelines for User Interface Design
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Provide feedback to users
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Display messages at a logical place on the
screen
Alert users to lengthy processing times or
delays
Allow messages to remain on the screen long
enough for users to read them
Let the user know whether the task or
operation was successful or not
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User Interface Design
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Guidelines for User Interface Design
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Create an attractive layout and design
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Use appropriate colors to highlight different
areas of the screen
Use special effects sparingly
Use hyperlinks that allow users to jump to
related topics
Group related objects and information
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User Interface Design
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Guidelines for User Interface Design
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Use familiar terms and images
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Remember that users are accustomed to a
pattern of red = stop, yellow = caution, and
green = go
Provide a keystroke alternative for each menu
command
Use familiar commands
Provide a Windows look and feel in your
interface design if users are familiar with
Windows-based applications
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User Interface Design
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User Interface Controls
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Menu bar
Toolbar
Command button
Dialog box
Text box
Toggle button
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User Interface Design
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User Interface Controls
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List box – scroll bar
Drop-down list box
Option button, or radio button
Check box
Calendar control
Switchboard
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User Interface Design
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User Interface Controls
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Event Modeling
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An action that triggers the system to
respond. i.e. receive EDI order, a sale,
end of work week, hire employee…
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Input Design
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Input technology has changed
dramatically in recent years
The quality of the output is only as
good as the quality of the input
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Garbage in, garbage out (GIGO)
Data capture
Data entry
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Input Design
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Input and Data Entry Methods
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Batch input
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Batch
Online input
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Online data entry
Source data automation
Magnetic data strips or swipe scanners
POS, ATMs
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Input Design
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Designing Data Entry Screens
Most effective method of online data
entry is form filling
Guidelines to help design data entry
screens
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Restrict user access to screen locations
where data is entered
Provide a descriptive caption for every field,
and show the user where to enter the data
and the required or maximum field size
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Input Design
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Designing Data Entry Screens
Guidelines to help design data entry
screens
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Display a sample format if a user must enter
values in a field in a specific format
Require an ending keystroke for every field
Do not require users to type leading zeroes
for numeric fields
Do not require users to type trailing zeroes
for numbers that include decimals
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Input Design
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Designing Data Entry Screens
Guidelines to help design data entry
screens
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Display default values so operators can
press the ENTER key to accept the
suggested value
Use a default value when a field value will
be constant for successive records or
throughout the data entry session
Display a list of acceptable values for fields,
and provide meaningful error messages
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Input Design
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Designing Data Entry Screens
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Guidelines to help design data entry
screens
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Provide a way to leave the data entry screen
at any time without entering the current
record
Provide users with an opportunity to confirm
the accuracy of input data before entering it
Provide a means for users to move among
fields on the form
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Input Design
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Designing Data Entry Screens
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Guidelines to help design data entry
screens
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Design the screen form layout to match the
layout of the source document
Allow users to add, change, delete, and view
records
Provide a method to allow users to search
for specific information
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Input Design
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Input Errors
At least eight types of data validation
checks
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Sequence check
Existence check
Data type check
Range check – limit check
Reasonableness check
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Input Design
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Input Errors
At least eight types of data validation
checks
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Validity check – referential integrity
Combination check
Batch controls
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Input Design
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Input Control
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Every piece of information should be
traceable back to the input data
Audit trail
Data security
Records retention policy
Encrypted – encryption
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Output Design Issues
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Before designing output, ask yourself
several questions:
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What is the purpose of the output?
Who wants the information, why it is it
needed, and how will it be used?
What specific information will be included?
Will the output be printed, viewed onscreen, or both?
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Output Design Issues
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Before designing output, ask yourself
several questions:
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When will the information be provided, and
how often must it be updated?
Do security or confidentiality issues exist?
Your answers will affect your output
design strategies
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Output Design Issues
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Types of Output
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In the systems design phase, you must
design the actual reports, screen forms,
and other output delivery methods
Internet-based information delivery
E-mail
Audio
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Printed Output
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Types of Reports
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Exception reports
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Are useful when the user wants information
only on records that might require action
Summary reports
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Reports used by individuals at higher levels in
the organization include less detail than reports
used by lower-level employees
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Printed Output
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User Involvement in Report Design
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Printed reports are an important way of
delivering information to users, so
recipients should approve all report designs
in advance
To avoid problems submit each design for
approval as it is completed, rather than
waiting to finish all report designs
Mock-up
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Printed Output
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Other Design Issues
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Good design standards produce reports
that are uniform and consistent
When a system produces multiple reports,
each report should share common design
elements
After a report design is approved, you
should document the design in a report
analysis form
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Chapter Summary
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The chapter began with a discussion of
human-computer interaction concepts and
graphical user interfaces (GUIs)
You learned that user-centered design
principles are used to understand the
business functions, maximize graphical
effectiveness, profile the system’s users, think
like a user, use prototyping, design a
comprehensive interface, continue the
feedback process, and document the interface
design
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Chapter Summary
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An effective way to reduce input errors is to
reduce input volume
The section on output included a discussion of
output design issues and a description of
various types of output
Finally, you learned about output control and
the various measures you can take to achieve
adequate output control to ensure that
information is correct, complete, and secure
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Chapter 7 Complete