phase 3. design phase chapter 7 – user interface, input, and output design

Phase 3. Design Phase

Chapter 7 – User Interface, Input, and Output Design

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

User Interface 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

Figure 7-2

User Interface Design

• Evolution of the User Interface– As information management evolved from

centralized data processing to dynamic, enterprise-wide systems, the primary focus also shifted — from the IT department to the users themselves

– User-centered system– Requires an understanding of human-

computer interaction and user-centered design principles

Figure 7-3 Figure 7-4

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

Figure 7-5 Figure 7-6

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

• Storyboard• Usability metrics

User Interface Design

• Basic Principles of User-Centered Design– Design a comprehensive interface– Continue the feedback process– Document the interface design

Figure 7-8

User Interface Design

• 8 Guidelines for User Interface Design– Good user interface design is based on a

combination of ergonomics, aesthetics, and interface technology

1. 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

User Interface Design

• Guidelines for User Interface Design2. 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

Figure 7-10

Figure 7-11

User Interface Design

• Guidelines for User Interface Design3. 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

Figure 7-12

Figure 7-13

Figure 7-14

User Interface Design

• Guidelines for User Interface Design4. 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

Figure 7-15

Figure 7-16

User Interface Design

• Guidelines for User Interface Design5. 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

Figure 7-17

User Interface Design

• Guidelines for User Interface Design6. 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

User Interface Design

• Guidelines for User Interface Design7. 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

User Interface Design

• Guidelines for User Interface Design8. 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

User Interface Design

• User Interface Controls– Menu bar– Toolbar– Command button– Dialog box– Text box– Toggle button

– List box – scroll bar– Drop-down list box– Option/radio button – Check box– Calendar control– Switchboard

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

Figure 7-21

Figure 7-22

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

Input Design

• Input and Data Entry Methods– Tradeoffs

• Unless source data automation is used, manual data entry is slower and more expensive than batch input because it is performed at the time the transaction occurs and often done when computer demand is at its highest

• The decision to use batch or online input depends on business requirements

Input Design

• Input Volume– Guidelines will help reduce input volume

1. Input necessary data only

2. Do not input data that the user can retrieve from system files or calculate from other data

3. Do not input constant data

4. Use codes

Input Design

• Designing Data Entry Screens– Most effective method of online data entry

is form filling– Guidelines will help you design data entry

screens1. Restrict user access to screen locations where

data is entered

2. Provide a descriptive caption for ever field, and show the user where to enter the data and the required or maximum field size

Input Design

• Designing Data Entry Screens– Guidelines will help you design data entry

screens3. 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

Input Design

• Designing Data Entry Screens– Guidelines will help you design data

entry screens7. 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

Input Design

• Designing Data Entry Screens– Guidelines will help you design data entry

screens10.Provide a way to leave the data entry screen at

any time without entering the current record11.Provide users with an opportunity to confirm the

accuracy of input data before entering it12.Provide a means for users to move among

fields on the form

Figure 7-24

Input Design

• Designing Data Entry Screens– Guidelines will help you design data entry

screens13.Design the screen form layout to match the

layout of the source document

14.Allow users to add, change, delete, and view records

15.Provide a method to allow users to search for specific information

Input Design

• Input Errors– Reducing the number of input errors improves

data quality– A data validation check improves input quality

by testing the data and rejecting any entry that fails to meet specified conditions

Input Design

• Input Errors– At least eight types of data validation

checks1. Sequence check

2. Existence check

3. Data type check

4. Range check – limit check

5. Reasonableness check

Input Design

• Input Errors– At least eight types of data validation

checks6. Validity check – referential integrity

7. Combination check

8. Batch controls

Figure 7-25

Input Design

• Source Documents– Source document – Form layout– Heading zone– Control zone– Instruction zone– Body zone– Totals zone– Authorization zone

Input Design

• Source Documents– Information should flow on a form from left to

right and top to bottom to match the way users read documents naturally

– A major challenge of Web-based form design is that most people read and interact differently with on-screen information compared to paper forms

Input Design

• Source Documents– Dr. Jakob Nielson believes that users scan a

page, picking out individual words and sentences

– As a result, Web designers must use scannable text to capture and hold a user’s attention

– Layout and design also is important on Web-based forms

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

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?

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

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

Figure 7-30

Figure 7-31

Output Design Issues

• Types of Output– Automated facsimile systems

• Faxback systems

– Computer output microfilm (COM)• Microfilm

– Computer output to laser disk (COLD)

Output Design Issues

• Specialized Forms of Output– An incredibly diverse marketplace requires

a variety of specialized output– Output from one system often becomes

input into another system– Although digital technology has opened

new horizons in business communications printed output still is the most common type of output

Printed Output

• Although many organizations strive to reduce the flow of paper and printed reports, few firms have been able to eliminate printed output totally

• Because they are portable, printed reports are convenient, and even necessary in some situations

• Turnaround documents

Printed Output

• Types of Reports– Detail reports

• Detail line• Control field• Control break• Control break report• Can be quite lengthy• Better alternative is to produce an exception

report

Figure 7-32

Figure 7-33

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

Figure 7-34

Figure 7-35

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

Printed Output

• Report Design Principles– Printed reports must be attractive,

professional, and easy to read– Report headers and footers– Page headers and footers– Column heading alignment

• Space columns of information carefully

Figure 7-36

Figure 7-37

Printed Output

• Report Design Principles– Field order

• Fields should be displayed and grouped in a logical order

– Grouping detail lines• It is meaningful to arrange detail lines in groups• Group header• Group footer

Printed Output

• Report Design Example– Revisit the Employee Hours report shown in

Figure 7-36. Although the report follows many of the design guidelines discussed, you still could improve it

– Too much detail is on the page, forcing users to search for the information they need

Figure 7-38

Figure 7-39

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

Printed Output

• Designing Character-Based Reports– Many systems still produce one or more

character-based reports– When report designers create or modify a

character-based report, they use a traditional tool that still works well, called a printer spacing chart

Figure 7-40

Printed Output

• Printing Volume and Time Requirements– High volume of reports can significantly

increase a system’s TCO– Length calculation– Time calculations

• Ppm (pages per minute)• Line printers

Figure 7-41

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