1. Adding Machine Prototype This is a bit trickier than the Tic Tac Toe prototype. It is not “clear” what should be included in the program (no rules). In this case, the stories will drive the interface design as well as the functions. It probably helps to identify GROUPS of functions. In “real” software, we see these in MENUES – so we can start with menues.

2. Adding Machine Prototype Storage Save Data Load Data Print Data Operations Add List Counting Items Averages/Stats Other Tools Windows Calculator MS Word These items came to mind at the beginning. We can add more later as we think of them. It probably makes sense to try to find a story for each of the menu items listed above – maybe one longer story for several items. You should find that your Intended User will be helpful by describing meaningful stories.

3. Adding Machine Prototype Stories First Rather than starting with the screen design, we can start with text stories, then design the screens, and then illustrate them.

4. Adding Machine Prototype Story : Adding Up a List The cafeteria, the book store and the bookkeeper add up lists of prices and money. Sometimes there are hundreds of numbers, so they need to be able to type them in quickly and easily, review them and find mistakes, and then change them easily. Then they want a total and maybe a printed copy of the list, nicely formatted.

5. Adding Machine Adding Up a List 25.00 23.25 19.95 8.50 99.00 17.99 17.99 Type number press [Enter] - automatically adds number to list Double-click to delete – confirmation question pops up Click OK to delete [ OK ] [ Cancel ] SAVE PRINT193.69 Total is always updated after adding or deleting Saves data in a disk file Prints a nicely formatted report on paper Loads list of data from a file LOAD Enter Data

6. Adding Machine Counting Items The user can type ranges (min, max) and immediately see the number of data items in that range. 0 SmallestLargest 19.993 # itemsPercent 50% 20.0049.99233% 50.0099.99117%

7. Adding Machine Statistics Max Item Min Item Total Average Standard Deviation 193.69 8.50 99.00 32.28 33.19

8. Adding Machine Prototype Automation Remember to keep notes about automation (processing) required for the stories and interfaces. For example: Calculate total, average, and standard dev Respond to double-clicks to delete Save and load data in disk files Right-alignment in text-fields and lists

9. Adding Machine Prototype Talk to the User Remember: the intended user will give you lots of good ideas about what your program needs to do and how it should work. Later your project will be assessed for usability and meeting goals. Let the user help you get a good grade.