1. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Starting Out with Programming Logic & Design Second Edition by Tony Gaddis Chapter 11: Menu-Driven Programs

2. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 11-2 Chapter Topics 11.1 Introduction to Menu-Driven Programs 11.2 Modularizing a Menu-Driven Program 11.3 Using a Loop to Repeat the Menu 11.4 Multiple-Level Menus

3. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 11-3 11.1 Introduction to Menu-Driven Programs A menu is a list of operations that are displayed by a program, in which a user can select which operations to perform Figure 11-1 A menu

4. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 11-4 11.1 Introduction to Menu-Driven Programs A decision structure can be used to perform menu selections –This can be accomplished through a case structure, series of nested if-then-else statements –A case structure is easier to follow the flow –A case structure will provide a case for each option in the menu, in addition to a default case

5. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 11-5 11.1 Introduction to Menu-Driven Programs Figure 11-2 Flowchart for Program 11-1

6. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 11-6 11.1 Introduction to Menu-Driven Programs Validating the menu selection can be done before the case is processed, allowing for no need for a default Display “Enter your selection” Input menuSelection //validation While menuSelection 3 Display “That is an invalid selection. Enter 1, 2 or 3” Input menuSelection End While

7. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 11-7 11.2 Modularizing a Menu-Driven Program Since a menu-driven program is capable of performing many tasks, it should be put into modules –A module should be written for each case that could be processed –The options would simply call modules –Allows for a clear flow of the program

8. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 11-8 11.2 Modularizing a Menu-Driven Program Figure 11-5 Flowchart for the main module in Program 11-3

9. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 11-9 11.3 Using a Loop to Repeat the Menu Most menu-driven programs use a loop to repeatedly display the menu after a task is performed –This allows the user of the program to run another option without restarting the program –The menu can also contain on option for ending the program Display “1. Convert inches to centimeters.” Display “2. Convert feet to meters.” Display “3. Convert miles to kilometers.” Display “4. End the program.”

10. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 11-10 11.3 Using a Loop to Repeat the Menu Figure 11-7 Flowchart for the main module in Program 11-5

11. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 11-11 11.4 Multiple-Level Menus A multiple-level menu has a main menu and one or more submenus –Some complex programs require more than one menu –A programmer should consider breaking up long menus into multiple menus –This is essentially nested case structures

12. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 11-12 11.4 Multiple-Level Menus Instead of this type of long menu 1.Process a sale 2.Process a return 3.Add a record to the inventory file 4.Search for a record in the inventory file 5.Modify a record in the inventory file 6.Delete a record in the inventory file 7.Print an inventory list report 8.Print a list of inventory items by cost 9.Print a list of inventory items by age 10.Print a list of inventory items by retail value

13. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 11-13 11.4 Multiple-Level Menus Convert to multiple menus such as Main Menu 1.Process a Sale or a Return 2.Update the Inventory File 3.Print an Inventory Report 4.Exit the Program Sales and Returns Menu 1.Process a Sale 2.Process a Return 3.Go Back to the Main Menu

14. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 11-14 11.4 Multiple-Level Menus More menus Update Inventory File Menu 1.Add a Record 2.Search for a Record 3.Modify a Record 4.Delete a Record 5.Go Back to the Main Menu

15. Copyright © 2010 Pearson Education, Inc. Publishing as Pearson Addison-Wesley 11-15 11.4 Multiple-Level Menus More menus Inventory Report Menu 1.Print an inventory list report 2.Print a list of inventory items by cost 3.Print a list of inventory items by age 4.Print a list of inventory items by retail value 5.Go Back to the Main Menu