---

Choosing a Graphical Environment for Your Application

Mac OS X offers many options for transforming your applications with a graphical user interface from a UNIX code base to a native Mac OS X code base, or even for wrapping preexisting command-line tools or utilities with a graphical front end, making them available to users who never want to go to the command line.

This chapter describes some of the issues you will face when porting a GUI application to Mac OS X or adding a GUI wrapper around a command line application. It also describes the various GUI environments supported by Mac OS X and gives advantages and disadvantages of each.

In choosing a graphical environment to use in bringing a UNIX-based application to Mac OS X, you will need to answer the questions posed in the following sections:

• “What Kind of Application Are You Porting?”

• “How Well Does It Need to Integrate With Mac OS X?”

• “Does Your Application Require Cross-Platform Functionality?”

These questions should all be evaluated as you weigh the costs and benefits of each environment. You may already be using a cross-platform toolkit API. If you aren’t doing so, you may want to port your application to a native API such as Carbon or Cocoa.

If you are a commercial developer adding a new graphical user interface to a command-line application and want to take advantage of the greatest strengths of Mac OS X, you will probably want to use the Cocoa API. In some cases, you may want to use a different API for reasons such as cross-platform compatibility.

If you decide to use a nonnative API, like X11R6, to provide a user interface for your Mac OS X application, it is important to remember that users and developers with a UNIX background might be perfectly content to just have the application running in Mac OS X. Traditional Macintosh users, however, will pass up an application with a traditional UNIX interface for a more integrated and modern interface. Whether you target a straight port to the Darwin layer or a more robust transformation of your application to take advantage of other Mac OS X technologies (like the Cocoa frameworks) is your decision.

---