chapter 7 user interface, input, and output design
TRANSCRIPT
Chapter 7
User Interface, Input, and Output Design
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Design Phase Description 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 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 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
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
Interactive feedback from stakeholder using a walk-thru demo to confirm requirements are being meet Storyboard Static Model Functional Model
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Total Cost of Ownership
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 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
Human-Computer Interaction 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 Human-Computer Interaction
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 Human-Computer Interaction
The user rights cited by Dr. Karat include Perspective Installation Compliance Instruction Control Feedback Dependencies Scope Assistance Usability
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User Interface Design Basic Principles of User-Centered
Design Understand the underlying business
functions Maximize graphical effectiveness Profile the system’s users Think like a user Use prototyping
Usability metrics
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User Interface Design
Basic Principles of User-Centered Design Design a comprehensive interface Continue the feedback process Document the interface design
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User Interface Design
Guidelines for User Interface Design Follow eight basic guidelines
1. Focus on basic objectives2. Build an interface that is easy to learn
and use3. Provide features that promote efficiency4. Make it easy for users to obtain help or
correct errors5. Minimize input data problems
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User Interface Design
Guidelines for User Interface Design Follow eight basic guidelines
6. Provide feedback to users7. Create an attractive layout and design8. 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
Guidelines for User Interface Design Focus on basic objectives
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
Guidelines for User Interface Design Build an interface that is easy to learn
and use 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 Guidelines for User Interface Design
Provide features that promote efficiency
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
Guidelines for User Interface Design Make it easy for users to obtain help or
correct errors Ensure that Help is always available Provide user-selected Help and context-
sensitive 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
Guidelines for User Interface Design Minimize input data problems
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 Guidelines for User Interface Design
Provide feedback to users 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
Guidelines for User Interface Design Create an attractive layout and design
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 Guidelines for User Interface
Design Use familiar terms and images
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
User Interface Controls Menu bar Toolbar Command button Dialog box Text box Toggle button
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User Interface Design
User Interface Controls 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
User Interface Controls
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Event Modeling
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
Input technology has changed dramatically in recent years
The quality of the output is only as good as the quality of the input Garbage in, garbage out (GIGO) Data capture Data entry
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Input Design
Input and Data Entry Methods Batch input
Batch Online input
Online data entry Source data automation Magnetic data strips or swipe scanners POS, ATMs
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Input Design Designing Data Entry Screens
Most effective method of online data entry is form filling
Guidelines to help design data entry screens
1. Restrict user access to screen locations where data is entered
2. 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 Designing Data Entry Screens
Guidelines to help design data entry screens
3. Display a sample format if a user must enter values in a field in a specific format
4. Require an ending keystroke for every field
5. Do not require users to type leading zeroes for numeric fields
6. Do not require users to type trailing zeroes for numbers that include decimals
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Input Design Designing Data Entry Screens
Guidelines to help design data entry screens
7. Display default values so operators can press the ENTER key to accept the suggested value
8. Use a default value when a field value will be constant for successive records or throughout the data entry session
9. Display a list of acceptable values for fields, and provide meaningful error messages
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Input Design Designing Data Entry Screens
Guidelines to help design data entry screens
10. Provide a way to leave the data entry screen at any time without entering the current record
11. Provide users with an opportunity to confirm the accuracy of input data before entering it
12. Provide a means for users to move among fields on the form
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Input Design
Designing Data Entry Screens Guidelines to help design data entry
screens13. Design the screen form layout to match
the layout of the source document14. Allow users to add, change, delete, and
view records15. Provide a method to allow users to
search for specific information
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Input Design
Input Errors At least eight types of data
validation checks1. Sequence check2. Existence check3. Data type check4. Range check – limit check5. Reasonableness check
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Input Design
Input Errors At least eight types of data
validation checks6. Validity check – referential integrity7. Combination check8. Batch controls
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Input Design
Input Control 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
Before designing output, ask yourself several questions: 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 on-
screen, or both?
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Output Design Issues
Before designing output, ask yourself several questions: 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
Types of Output 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
Types of Reports Exception reports
Are useful when the user wants information only on records that might require action
Summary reports 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 User Involvement in Report Design
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 Other Design Issues
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 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 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
Chapter 7 Complete