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Defining the Controller Class

Interface Builder is a versatile tool for application developers. It enables you to not only compose the application’s graphical user interface, it gives you a way to define much of the programmatic interface of the application’s classes and to connect the objects eventually created from those classes.

The rest of the chapter shows how to define the ConverterController class and connect it to Currency Converter’s user interface.

In Xcode, choose File > New File.

1. Select the Classes group in the Groups and Files list.

2. Choose Objective-C Class and click Next.

3. Name the file ConverterController.m.

4. Make sure “Also create ‘ConverterController.h’” is selected and click Finish.

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