A Final Word About Macintosh

If you are one a Windows machine and compile a Mac OS X application with the Professional Edition, you might be surprised to see that instead of an application icon you see a folder. That's because Macintosh OS X uses the concept of bundles.

Macintosh Bundles

A file isn't always just a file. There are certain cases when the user interface makes a folder look like an individual file. If you are compiling applications for OS X, you will encounter Macintosh bundles, which are a collection of folders and files that look like a file on Macs.

Prior to OS X, Macintosh used a proprietary file format to group related resources used by a file (or application). This format used two forks, a resource fork and a data fork. Although OS X has dispensed with the idea of resource forks in favor of something called bundles, the term resource is still used a lot (and is referred to in the REALbasic documentation). Figure 4.18 illustrates the folders and files that make up a bundle. These days, you can have a resource file that contains icons, strings, and pictures that you can access from REALbasic. I would strongly advise you to avoid creating any application that uses a resource file and instead either import any graphics you need into the REALbasic application itself, or access the files from the file system.

Figure 4.18. Application Bundle.