Chapter 7. Dragging, Rotating, and Scaling

In this chapter, we'll be tackling our ninth programming exercise together. This app will be one of your first to include an advanced feature of iPhone and iPad apps: the ability to drag, rotate, and scale objects on the screen with your fingers. This is just one of the unique features of the iPhone and iPad that have contributed to their phenomenal success.

The ability to interact directly with items on the screen–in an easy and intuitive way–is very important for your application. Capitalizing on this integral feature, by accommodating these natural actions, is what we're after in this chapter. We will consider these interactions from the underside of the application–in the same way that mechanics raise ...

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