1. Intro To Design 1
Elementary School Library: User Sub-System Class Diagrams
Software Engineering
CSCI-3321
Dr. Tom Hicks
Computer Science Department

2. "Good Design Is Good Design"
Language Independent!
Data Independent  Database Table Direct Access File  Text File
Should Not Have Multiple Copies Of Redundant Data
 Never Makes Sense To Lock & Change Multiple Records When We Could Lock & Change One Record!

3. Select A Team Recorder  Take Really Good Notes During Lectures

4. Begin With The End In Mind!

5. Your Application  3+ Simple Sub-Systems & 2+ Transactions
All applications will need several forms.
Most users will prefer you bind them in an MDI (Multiple Document Included Container)

6. You Will Need An Easy/Obvious Way To Get To Your Forms
MenuStrips Will Help!
Always Save The User As Many Clicks As Is Possible!

7. MDI Containers Can Have A Background
Select A Good, Professional Background For Your Application

8. Sub-Systems Must Have Navigation Buttons
You Will Need Navigation Buttons
 Buttons Need Not Look Like = = = = = = = >
Must Have:
Next: Go To The Next Logical Record
Previous: Go To The Next Logical Record
First: Go To The First Logical Record
Last: Go To The Last Logical Record

9. Use Good Tool Tips On Each & Every Button
Navigation Buttons
Download/Make Your Own - HOPE THEY ARE BETTER THAN MINE!
Use
Use Good Tool Tips On Each & Every Button

10. I have found that Users like Quick Link Buttons!

11. Class Diagrams
Help Identify
Data

12. Use Excel For Class Diagrams We Want To Identify & Organize All Of The User Information For Folks Checking Out Books, Magazines, Tapes, ETC.
Non Students?

13. Must Be Able To Uniquely Identify Each User
ID  Auto Incrementing Primary Key?
May Seem Database Related  BUT IT IS NOT! CAN DO WITH Direct Access Files, ISAM, BTrees, etc.

14. We Need A Name Field Right?
If Only Name Field!

15. First & Last Name Should Be Separate Fields
Order Records By Name  Like Phone Book!
Database - Don't Store Multiple Pieces Of Info In A SIngle Container

16. Search By Name Search By First Reports
Order By Name  Like Phone Book!

17. All Of Us Are Going To Include Name Info

18. Better Yet All Of Us Are Going To Include Name Info

19. Now Suppose I Included A UserType Field
Student
Teacher
Librarian
Parent
Take 1 Minute With Your Team
List Different User Types For The Elementary School Library Application

20. Class Diagrams Done For Stakeholder Done For Developer Team

21. Most Software Engineers Include The "Brief Class Diagram"
Which Are Required?
What Type Of Control On The Screen?
Default Values?

22. Class Diagram:Detailed  My Preferences
Students
Teachers
Students
Teachers
Librarians
Guests
Students
Teachers
Librarians
Parents
Guests
Lots Of Options On What To Include

23. Select Filters  Help You Drill Down Into The Data
SELECT * FROM Users WHERE UserType Like "Guests";

24. If You Hard Code Data Into Combo Control  Change?
3] If You Hard Code The Filter, It Would Require A Programmer To Modify The Code To Change It  YUK!
4] Numeric Queries Are Much Slower Than Text Queries - Whether You Use A Database Or Not!
SELECT * FROM Users WHERE UserType = 3 ?

25. This Design Stinks!
1] Software Engineer Is Expecting Users To Know All The Choices For UserType!
Students
Teachers
Librarians
Parents
Guests
2] Software Engineer Is Expecting Users To Be Able To Spell The Choices Correctly!

26. "Good Design Is Good Design"
Store The Data  Database Table  Direct Access File  Text File
API  Application Programming Interface
We Can Fill ComboBox Controls (Web/API) With UserTypes  Selection Return A String
Fill Control From Query Or Array
Fill With One Item  UserType  Return String
Fill With Two Items  UserType & ID  Return Numeric

27. Populating The Combo Control Is Generally 1 Line Of Code!
Suppose We Use A Database : Data Entry Field For User
Connecting To The Database Is Generally 1-2 Lines Of Code!
Populating The Combo Control Is Generally 1 Line Of Code!
Data Entry

28. Populating The Combo Control Is Generally 1 Line Of Code!
Suppose We Use A Database : Filter
Connecting To The Database Is Generally 1-2 Lines Of Code!
Populating The Combo Control Is Generally 1 Line Of Code!
FILTER

29. UserTypes Interface ?
One Of The Teams, Last Year, Did A Complete Sub-System Interface (Next, Previous, First, Last, Edit,
OVER-KILL  Too Much Work  UserType Is A Supporting Class

30. More Appropriate UserTypes Interface ?
No Re-Programming!

31. UserType Is A Supporting Class Of User
A Supporting Class May Support More Than One Class
 Great Idea To Provide

32. Class Diagrams: Detailed
Detailed Class Diagrams Can
Occupy A Lot Of Real Estate?

33. What Type Of Control? What DataType?
Back To Class Diagram
What Type Of Control?
What DataType?

34. User Sub-System Class Diagrams: Brief
As You Meet With Your Stakeholder, You Go Through The Fields In The UserType
 "What Have I Missed" - Additional ?  "What Do I Have That You Don't Want?"
It Would Be Good To Show
 So That They Would Have A Better Understanding Of UserTypes! OR
 Them Might Even Add Additional Options To Data