Inside Macintosh: QuickDraw GX Environment and Utilities /

Chapter 4 - QuickDraw GX Debugging

This chapter describes the QuickDraw GX application debugging environment and the functions and utilities that you can use to debug your application. Read this chapter if you are developing a QuickDraw GX application and want to use these features.

Before reading this chapter, you should be familiar with the debugging and non-debugging versions of QuickDraw GX described in the chapter "Errors, Warnings, and Notices" in this book. You should also read the chapter "Introduction to QuickDraw GX" in Inside Macintosh: QuickDraw GX Objects.

For more information on debugging printing applications, see Inside Macintosh: QuickDraw GX Printing and Inside Macintosh: QuickDraw GX Printing Extensions and Drivers.

This chapter introduces the QuickDraw GX debugging environment. It then describes how to use this environment during application development to

• analyze drawing problems
• validate public and internal function parameters for all allocated objects
• validate public and internal function parameters for specific objects
• distinguish between application and QuickDraw GX bugs
• detect corrupted objects
• install a debugging function
• use the GraphicsBug utility

This chapter also contains reference information for all data types and functions associated with QuickDraw GX debugging.

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Chapter Contents

About QuickDraw GX Debugging

Debugging Version of QuickDraw GX

QuickDraw GX Errors, Warnings, and Notices

Application-Defined Error, Warning, and Notice Handlers

The Drawing Error Function

Validation Functions

MacsBug and GraphicsBug

Using QuickDraw GX Debugging

Analyzing Drawing Problems

Using Validation Functions

Controlling Validation

Type Validation

Structure Validation

All Object Validation

Memory Validation

Validating Objects

Analyzing the Cause of Validation Errors

Distinguishing Between Application Bugs and QuickDraw GX Bugs

Detecting Corrupted Objects

Debugging With GraphicsBug

Analyzing a Picture Shape

Determining the Heap Size for All Shapes in the Picture

Analyzing the Shapes in the Picture

Analyzing the Rectangle in the Picture

Analyzing the Ink in the Rectangle

QuickDraw GX Debugging Reference

Constants and Data Types

Drawing Errors

Validation Levels

Functions

Obtaining Drawing Errors

Setting and Getting Validation Options and Errors

Validating Objects

Summary of QuickDraw GX Debugging

Constants and Data Types

Drawing Errors

Validation Levels

Functions

Obtaining Drawing Errors

Setting and Getting Validation Options and Errors

Validating Objects