Travel Advisor has three classes: Country, Converter, and TAController. Only TAController has outlets and actions. And, rather than defining the Converter class, you are simply going to add it to the project from the Currency Converter project and reuse it.
Subclass NSObject to create the Country and TAController classes.
In Interface Builder, bring up the Classes display of the nib file window.
Select NSObject as the superclass.
Choose Subclass from the Classes menu.
Country in place of
Repeat for TAController.
Now that the interface has been laid out, you can define the outlets that let TAController communicate with the UI objects. While here, you can also add the outlet for the Converter object that will be reused from the Currency Converter project.
Select TAController and choose Add Outlet from the Classes menu.
Add the following outlets:
In addition to outlets, you must specify actions so that the UI objects can message TAController.
Select TAController and choose Add Action from the Classes menu:
Define the following action methods: