Chapter 7
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Presentation Transcript
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
