4. Visual Effects

Well, circles and ovals are good, but how about drawing rectangles with rounded corners? Can we do that now, too?

Steve Jobs

We looked at the layer frame in Chapter 3, “Layer Geometry,” and the layer backing image in Chapter 2, “The Backing Image.” But layers are more than mere rectangular containers for colors or images; they also have a number of built-in features that make it possible to create impressive and elegant interface elements programmatically. In this chapter, we explore the various visual effects that can be achieved using CALayer properties.

Rounded Corners

One of the signature features of the iOS aesthetic is the use of rounded rectangles (rectangles with rounded corners). These appear everywhere in iOS, from ...

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