n User Interface, Input and Output Design - peter-lo.com

1 user interface Design n user interface Design requires an understanding of user interface , Human-Computer Interaction (HCI) and user - Input and Output Design centered Design principles. Peter Lo CS211 Peter Lo 2004 1 CS211 Peter Lo 2004 2. 8 user -centered Design Principles Good user interface Design 1. Understand the Underlying Business Functions n Good user interface Design is based on a 2. Maximize Graphical Effectiveness combination of Ergonomics ( ), Aesthetics ( ), and interface Technology. 3.

2 Profile the System's Users u Ergonomics How people work, learn and 4. Think like a user interact with computer. 5. Use Prototyping u Aesthetics How an interface attractive and 6. Design a Comprehensive interface easy to use. u interface Technology Provide the operational 7. Continue the Feedback Process structure for Design objective. 8. Document the interface Design CS211 Peter Lo 2004 3 CS211 Peter Lo 2004 4. 1. user interface Design Guidelines user interface Controls n Focus on Basic Objectives n The designer can include many control features, n Build an interface that is Easy to Learn and Use such as Menu Bars, Toolbars, Dialog Boxes, Text n Provide Features that Promote Efficiency Boxes, Toggle Buttons, List Boxes, Scroll Bars, n Make it Easy for Users to Obtain Help or Correct Errors Drop-down List Boxes, Option Buttons, Check n Minimize Input Data Problems Boxes, Command Buttons, Spin Bars.

3 And n Provide Feedback to Users Calendars among others. n Create an Attractive Layout and Design n Use Familiar Terms and Images CS211 Peter Lo 2004 5 CS211 Peter Lo 2004 6. user interface Controls Input Design Issues n Data Capture is the identification and recording of source data. n Data Entry is the process of converting source data into computer-readable form and entering it into the information system. CS211 Peter Lo 2004 7 CS211 Peter Lo 2004 8. 2. 6 Main Input Design Objectives Input and Data Entry Methods 1.

4 Select a suitable Input and data entry method n Input processes should be efficient, timely and logical. 2. Reduce Input volume n Two major Input methods: u Batch Input 3. Design attractive data entry screens t Data entry is performed on a specified time schedule, 4. Use validation checks to reduce Input errors such as daily, weekly, monthly, or longer. 5. Design required source documents u Online Input 6. Develop effective Input controls t Offers major advantages, including the immediate validation and availability of data.

5 CS211 Peter Lo 2004 9 CS211 Peter Lo 2004 10. Input Volume Data Entry Screens Design n To reduce Input volume, you must reduce the n Restrict user access. number of data items required for each transaction. n Provide a descriptive caption. n Display a sample format n Guidelines: n Require ending keystroke for every field. u Input necessary data only. n Do not require users to type leading zeroes for numeric u Do not Input data that the user can retrieve from fields. system files or calculate from other data.

6 N Do not require users to type trailing zeroes for numbers that include decimals. u Do not Input constant data. n Display default values. u Use codes. n Use a default value when a field value will be constant. CS211 Peter Lo 2004 11 CS211 Peter Lo 2004 12. 3. Data Entry Screens Design Input Errors Validation n Display list of acceptable values. n Reducing the number of Input errors improves data quality. n Provide a way to leave the data entry screen at any time. n Some data validation checks: n Provide users with an opportunity to confirm the accuracy u Sequence checks.

7 Of Input data before entering it u Existence checks. n Provide a means for users to move among fields on the u Data type checks. form in a standard order or in any order they choose. u Range checks. n Design the screen form layout to match the layout of the u Reasonableness checks. source document. u Validity checks. n Allow users to add, change, delete, and view records. u Combination checks. n Provide a method to allow users to search for specific u Batch controls. information. CS211 Peter Lo 2004 13 CS211 Peter Lo 2004 14.

8 Source Documents Design Input Control n A source document is a form used to request and n Input control includes the necessary measures to ensure collect Input data, trigger or authorize an Input that Input data is correct, completed and secure. u Audit trail action, and provide a record of the original transaction. tRecords the source of each data item and when it entered the system. Show how and when data is accessed or changed, and by whom. u Data security t Protects data from lost or damage and recovers data when it is lost or damaged.

9 CS211 Peter Lo 2004 15 CS211 Peter Lo 2004 16. 4. Output Design Issues Types of Output n Some questions to consider before designing Output : n Internet-Based Information Delivery. u What is the purpose of the Output ? n E-Mail. u Who wants the information, why it is needed, and how n Audio Output . will it be uses? u What specific information will be included? n Automated Facsimile Systems. u Will the Output be printed, viewed on-screen, or both? n Computer Output Microfilm (COM). u When will the information be provided, and how often must it be updated?

10 U Do security or confidentiality issues exist? CS211 Peter Lo 2004 17 CS211 Peter Lo 2004 18. Specialized Forms Of Output Printed Output n Retail point-of-sale terminals n Detail Report u A detail report produces one or more lines of Output for n Automated teller machines (ATM). each record processed. Each line of Output printed is n Special-purpose printers called a detail line. n Plotters n Exception Report n Digitized photos uAn exception report displays only those records that meet a specific condition or conditions.