Learning Carbon

Chapter 13. Desktop Icons

The Finder, the application that manages the user interface in Mac OS X, represents the file system to the user through the metaphor of a desktop with folders and documents on it. Those ubiquitous little pictures called icons are the heart of the desktop metaphor because they represent documents, storage media, folders, and applications to the user. By manipulating icons, the user can conduct such operations as launching applications, opening folders, and moving files.

Graphic limitations of earlier operating systems constrained icons to a two-dimensional style. Mac OS X icons, on the other hand, are capable of having depth and a lush look that approaches photo-realism.

When you create an application, the operating system will assign it a generic icon unless you provide your own custom icon. While not entirely unappealing, a generic icon doesn’t communicate anything to the user about an application. To make your application complete, you should provide a custom icon. If your application creates documents or uses plug-ins or other files, you should provide icons for those as well. In this chapter, you’ll:

• Take a look at the kinds of icon that are used on Mac OS X

• See what goes into icon design

• Look at the technical details of icons, such as sizes and masks

• Find out how to get a file or application to appear with your icon

• Add application and document icons to the Moon Travel Planner application

Icon Basics

Creating icons requires artistic and technical skills. ...