6ed-Solutions-Chap07.doc

Systems Analysis and Design in a Changing World, sixth edition

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Chapter 7 – Designing the User and System Interfaces Solutions to End-of-Chapter Problems Review Questions 1. Why is interface design often referred to as dialog design? The user interface involves communication between the user and the computer, which is much like a dialog. One of the metaphors for designing the user interface is called the dialog metaphor. 2. What are the three aspects of the system that make up the user interface for a user? Physical, perceptual, and conceptual aspects. (p189) 3. What are some examples of the physical, perceptual, and conceptual aspects of the user interface?  Keyboard, mouse, touch screen, reference manuals, documents, data entry forms.  Data on the screen, shapes, lines, numbers, words, beeps, clicks, menus, dialog boxes, icons, drawings.  Conceptual aspects of the user interface include everything the user knows about using the system, including all of the problem domain “things” in the system the user is manipulating, the operations that can be performed, and the procedures followed to carry out the operations. 4. What are the four metaphors used to describe human-computer interaction? Direct manipulation metaphor, desktop metaphor, document metaphor, and dialog metaphor. 5. A desktop on the screen is an example of which of the metaphors used to describe humancomputer interaction? This started as a direct manipulation metaphor, which over time grew into the desktop metaphor itself. 6. What type of document allows the user to click a link and jump to another part of the document? Hypertext 7. List and briefly describe four guidelines for interface layout and formatting that apply to all types of user display and input devices. What additional guidelines apply to Web sites/pages and user interfaces for mobile computing devices?


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 Consistency—All the forms within a system need to have the same look and feel. Consistent use of function keys, shortcuts, control buttons, color, and layout makes a system much more useful and professional looking.  Labels and headings—Labels should also be easy to identify and read. A clear, descriptive title at the top of the interface helps to minimize confusion about a form’s use.  Distribution and order—Related fields are usually placed next to each other and can be grouped within a box. Tab order should follow the users’ usual reading order.  Fonts and colors—Variations in font face and size can help users distinguish different parts of the form, but only a handful of font and size variations should be used for larger screens and as few as possible should be used for small screens. Additional guidelines for Web sites and mobile devices include:  Consistency  Performance  Pictures and video display  Users with disabilities  Small screen sizes 8. What is the technique that shows a sequence of sketches of the display screen during a dialog? Storyboarding 9. What UML diagram can be used to show how the interface objects are plugged in between the actor and the problem domain classes during a dialog? [This question should have been deleted.] Sequence diagram and communication diagrams. (See Chapter 11.) 10. What are some of the input controls that can be used to select an item from a list? List boxes and combo boxes. Radio buttons and check boxes also show lists (or groups). 11. What two types of input controls are included in groups? Groups are radio buttons and check boxes. 12. What popular analogy is used for direct customer access with a Web site when customers shop online? Shopping cart analogy. 13. What does XML stand for? Explain how XML is similar to HTML. Also discuss the differences between XML and HTML. XML stands for Extensible Markup Language. It is similar to HTML in that it has tags that are used to identify groups of elements. It also allows nested tags. However, in XML the tags are


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user defined and must be done with another data definition file to define what the tags are and how they relate to each other. 14. How do you identify the data fields of a system interface by using UML and the objectoriented approach? In a system sequence diagram, the parameters on the input messages are the data fields that are passed into the system (e.g. to the user interface) from the user. 15. What are the different considerations for output screen design and output report design? Output screens are more dynamic but have limited information available at one time. It is harder to view multiple pages at the same time with screen output. However, dynamic features, such as drill down, can be provided so that summary information does not have to stand alone. Printed output is more permanent. Consequently, it should always include identifying fields, such as date printed. Because reports are not dynamic, they must be self-contained and include all necessary information to be understandable. 16. What is meant by drill down? Give an example of how you might use it in a report design. Drill down means the ability (with online reports or output screens) to select a field and “drill down” to show more detail on the data in that field. It is often used on summary reports. Clicking on a summary amount, for example a yearly total, could open up another window showing the month by month totals. 17. What is the danger from information overload? What solutions can you think of to avoid it? Information overload can cause users to miss important facts, such as exception conditions. Users can also become discouraged when they are unable to find the information they need within reams of unimportant data. Solutions generally include identifying the information that is important and highlighting it using color or graphics, or by visually separating it from the other data.


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Problems and Exercises 1. Think of all the software you have used. What are some examples of ease of learning conflicting with ease of use? Answers will vary. Students might discuss the difficulty of a multi-level menu selection where a hot key to go directly to a screen would facilitate ease of use. Students might also mention some websites, maybe even Amazon, where there is no obvious hot link to another page, so the user must navigate either with the back button or with a menu hierarchy. 2. Visit some Web sites and then identify all the controls used for navigation and input. Are they all obvious? Discuss some differences in visibility and affordance among the controls. Answers will vary. Most sites have good affordance and visibility, but sometimes there will be a file download or an update to a field that is not obvious that it has completed. Web sites include many clickable objects. It is hard to tell which objects can be clicked and which cannot. Many objects do not indicate that they have been clicked. In addition, it is not always easy to tell what the control does—does it go to another part of the current page, to another page at the site, or to another site altogether? 3. A common maxim for designing a man-machine interface is that it is better to change the machine than to try to change the human to accommodate the machine. Are there machines (or systems) that you use in your daily life that have room for improvement? Are the current generations of Windows PC and Apple Mac as usable as they might be? If not, what improvements can you suggest? Is the World Wide Web as usable as it might be? If not, what improvements can you suggest? Are we just beginning to see some breakthroughs in usability, or have most of the big improvements already been made? Student solutions will vary (probably wildly). Some students might want to compare Windows and Mac interfaces with other user interfaces on physical devices. Some devices for comparison might be:  automobile user interfaces (with GPS, mobile phone, etc.)  home appliances (microwave and other programmable devices)  home entertainment systems (TV, DVRs, DVD players, etc.) 4. Download and install App Inventor from Google. Use it to develop a prototype interface that implements the storyboard in Figure 7-7. Student solutions will vary. 5. Evaluate the course registration system at your university. List the basic steps of a user’s dialog with the system. What are some of the problems with the system from the perspective of


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ease of learning and ease of use? In what ways is the system inflexible? In what ways is needed information not available? Is too much information provided that distracts from the task at hand? Student solutions will vary. 6. Evaluate the online catalog system at your university library. Write a dialog that shows the interaction between the user and the system. Rewrite the dialog to improve it. Create a storyboard to show how your design would look and feel. Student solutions will vary. 7. Find a Web site with direct customer ordering. Browse through some product descriptions and note the design of the dialog and the Web pages. What do you like and dislike about the design? Evaluate the Web site based on visibility and affordance. Does the site achieve an optimal balance between the number of page refreshes and the delay between page refreshes? Would your answer change if you were using a different computing device, a different network, or accessing the system at a different time of day? Student solutions will vary. The instructor might want to suggest some specific company websites.


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Solutions to End-of-Chapter Cases Case Study: Video Rental Service Develop a storyboard that encompasses the following sample dialog. The system supports rental and download of movies or television shows to a computer or digital video recording and playback device. A dialog between the system and user might follow this pattern:


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Running Cases: Community Board of Realtors One of the key use cases for the multiple listing service system is Create new listing, where the Realtor enters all the important information about a new listing he or she has obtained. Consider the information that must be entered when creating a new listing, and list the dialog steps that are necessary. Keep in mind that when designing for a smartphone, less information can be entered in each step compared to a full screen Web application. Also keep in mind that typing is errorprone and awkward for many users, so think about opportunities to use check boxes, radio buttons, and list boxes to aid selection. Create a storyboard of this use case for a mobile device, showing each step of the dialog that maximizes the use of check boxes, radio buttons, and list boxes.

Answers will vary: Designing smartphone apps is a whole new endeavor and quite different from normal browser based apps. The following design is based on one screen to act as a menu screen (what to do). The second screen allows entry of all the data. It is on one screen which is a scrolling screen with data entry on entire screen. Again for smartphone apps, there are combinations of screen data entry, keyboard, Save hot link – sometime on the screen, sometimes on the keyboard, and settings popup menu option.


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Running Cases: The Spring Breaks 'R' Us Travel Service Imagine resort security with a large, wide-screen monitor tracking traveler activities. Design a main screen that includes multiple locations, paths and roads, traveler location and status, messages traveling from traveler to traveler, and other features that security should monitor. Create a storyboard that shows an example of a pop-up alert and a menu of options that security might select after an alert. Should you also show security the staff members’ locations and status? How about clicking security staff members to send them a message? How about clicking a location to turn up the lights or to close a security gate? Be creative as you think through the design possibilities. You should include four or five screen layouts for the storyboard.

Student answers will vary. Here is an example of a main screen and four popups.


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Running Cases: On the Spot Courier Services Review the case description and your solution for the Web scenario of the use case Request package pickup from Chapter 5. Then, using a presentation tool, such as Microsoft PowerPoint or Apple Keynote, create a storyboard of the Web pages necessary to support the use case. The case description in Chapter 5 also identified a new use case, which we can call View scheduled pickups/deliveries. Based on current technology, write a dialog showing how this might be supported with a portable digital device. You may use any current technology that you deem applicable, such as GPS tracking, map and directions software, and real-time updates of pickup locations. Consider the possibility that the driver may want to get an overview of his or her stops for the entire run, view the next few stops, or just get directions to the next stop.


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Dialog for Driver and System: System: What do you what to do? Driver: Give me the address of the next stop. System: It is a delivery at this address ---Driver: How far is that from where I am now? System: 6.3 miles Driver: Can you show me the best route to get there? System: Here is a map showing the shortest route using primary roads. Do you want printed instructions? Driver: No Driver: How many pickups do I have left today? System: 14 Driver: How many deliveries do I still have? System: 37 Driver: Show me the next 5 System: Here is a list. Do you want to see a map? Driver: Yes. Show me a map of the next five stops. System: OK Driver: Do you have any new additions that have come in? System: Yes. There is one new pickup recently received. It will be best to pick it up on the return trip to the warehouse.


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Running Cases: Sandia Medical Devices No industry group has yet defined XML tags suitable for the RTGM application. Thus, designers must develop appropriate tags for this application. If you aren’t already familiar with XML, do at least 30 minutes of background research on the Web. Refer to the class diagram in the Chapter 4 RTGM case to determine required data content. Then, design XML tags and message formats suitable to transmit timestamped glucose levels from the cell phone app to the server and to transmit updated alert conditions from the server to the cell phone app. If medical personnel choose to send a text message to the patient, how will the server transmit that message? To help answer that question, research Short Message Service (SMS), Enhanced Messaging Service (EMS), and SMS gateways.

Glucose Level sample tags 2342394287 7343-34535-4654 2/22/2013; 22:29:38 95 mgl 555-345-5678 5.3 Return Alert Message 2342394287 7343-34535-4654 Smith 2/22/2013; 22:29:38 Your glucose level is approaching critical levels at 190 mgl level. Please take another dosage of medication. Messages will be transmitted through normal SMS gateways to send an SMS message to the users cell phone. The user should open up the app and send a response that the instruction was received.

6ed-Solutions-Chap07.doc

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