Inside Macintosh: Operating System Utilities /

Chapter 5 - Control Panel Extensions

This chapter describes how you can create a control panel extension to add a panel to an existing control panel. Some of the control panels provided with the Macintosh system software allow you to install additional panels to control settings for your own devices. You can also install additional panels to allow the user to manipulate other system-wide settings or configuration data not directly associated with any hardware.

You need to read this chapter if you are developing hardware or software that provides system-wide services and that has one or more settings that a user might want to alter. However, you need to read this chapter only if some existing control panel is extensible in the way described in the next section, "About Control Panel Extensions." Currently, only certain versions of the Sound control panel and the Video control panel allow you to add panels by creating control panel extensions. In all other cases, you'll need to create a control panel to handle any necessary user interaction. For a complete description of how to create a control panel, see the chapter "Control Panels" in Inside Macintosh: More Macintosh Toolbox. (Also see the chapter "Control Panels" if you are the manufacturer of a video card and need to create an extension to the Monitors control panel.)

To use this chapter, you should already be familiar with creating dialog boxes and handling user actions in them. See the chapters "Dialog Manager" and "Event Manager" in Inside Macintosh: Macintosh Toolbox Essentials for more information about these topics. Because control panel extensions are components, you also need to be familiar with the Component Manager, described in Inside Macintosh: More Macintosh Toolbox.

Note

The programming interface to control panel extensions described in this chapter is virtually identical to the programming interface to sequence grabber panel components, described in the chapter "Sequence Grabber Panel Components" in Inside Macintosh: QuickTime Components. If you are programming in C, you might find it useful to consult the source code samples, which are in C in that chapter.

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Chapter Contents

About Control Panel Extensions

Writing a Control Panel Extension

Creating a Component Resource for a Control Panel Extension

Dispatching to Control Panel Extension-Defined Routines

Installing and Removing Panel Items

Handling Panel Items

Handling Events in a Panel

Handling Title Requests

Managing Control Panel Settings

Control Panel Extensions Reference

Control Panel Extension-Defined Routines

Managing Panel Components

Handling Panel Events

Managing Panel Settings

Summary of Control Panel Extensions

Pascal Summary

Constants

Control Panel Extension-Defined Routines

C Summary

Constants

Control Panel Extension-Defined Routines