4-7: Check Box and Option Controls

Exercise 4-6: Testing the Program

This program demonstrates how in some situations the need for user input by typing can be eliminated. This might often simplify the code, removing the need to validate user input. However, it is still necessary to test the code, of course. It is always possible - indeed, quite likely - that the interface does not work as you expect.

So carefully test the program. Here are a few things to look for:

• can only one option button be selected at a time?
• are the checkboxes enabled after the time option is selected? and disabled when the Next Customer button is pressed?
• do the interface objects associated with a ticket type appear and disappear as expected? particularly when the quantity is decreased using the - command button from 1 to 0?
• are the prices calculated correctly?
• are you happy with what happens if the user changes the movie or movie time selection after they have selected some quantity of tickets?

We'll possibly return to this exercise in later sections, since it has the potential for many interesting developments!