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Chapter 7. User Interface, Input, and Output Design. 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
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Chapter 7 User Interface, Input, and Output Design
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
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
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
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
Prototyping • Interactive feedback from stakeholder using a walk-thru demo to confirm requirements are being meet • Storyboard • Static Model • Functional Model
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
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
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
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”
User Interface Design • Human-Computer Interaction • The user rights cited by Dr. Karat include • Perspective • Installation • Compliance • Instruction • Control • Feedback • Dependencies • Scope • Assistance • Usability
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
User Interface Design • Basic Principles of User-Centered Design • Design a comprehensive interface • Continue the feedback process • Document the interface design
User Interface Design • Guidelines for User Interface Design • Follow eight basic guidelines • 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
User Interface Design • Guidelines for User Interface Design • Follow eight basic guidelines • 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
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
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
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
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
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
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
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
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
User Interface Design • User Interface Controls • Menu bar • Toolbar • Command button • Dialog box • Text box • Toggle button
User Interface Design • User Interface Controls • List box – scroll bar • Drop-down list box • Option button, or radio button • Check box • Calendar control • Switchboard
User Interface Design • User Interface Controls
Event Modeling • An action that triggers the system to respond. i.e. receive EDI order, a sale, end of work week, hire employee…
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
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 • Designing Data Entry Screens • Most effective method of online data entry is form filling • Guidelines to help design data entry screens • 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
Input Design • Designing Data Entry Screens • Guidelines to help design data entry screens • 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
Input Design • Designing Data Entry Screens • Guidelines to help design data entry screens • 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
Input Design • Designing Data Entry Screens • Guidelines to help design data entry screens • 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
Input Design • Designing Data Entry Screens • Guidelines to help design data entry screens • 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
Input Design • Input Errors • At least eight types of data validation checks • Sequence check • Existence check • Data type check • Range check – limit check • Reasonableness check
Input Design • Input Errors • At least eight types of data validation checks • Validity check – referential integrity • Combination check • Batch controls
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
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
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 • 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
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
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