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Issue 2.3

COLUMN

Object-Oriented Callbacks

Issue: 2.3 (December/January 2003)
Author: Charles Yeomans
Author Bio: Charles Yeomans is a software developer in Lexington, Kentucky.
Article Description: No description available.
Article Length (in bytes): 5,376
Starting Page Number: 36
Article Number: 2316
Related Web Link(s):

http://www.quantum-meruit.com/RB/WindowMenu.sit
http://www.quantum-meruit.com/RB/SortLibrary.sit
http://developer.apple.com/technotes/tn/tn2009.html

Excerpt of article text...

A callback is a technique in which one passes a function pointer to another function or data structure; this function pointer can then be called at some later point in time. This bit of indirection is a standard trick in C programming. However, REALbasic doesn't support pointer programming. To see how to implement callbacks in REALbasic, let's take a look at some basic problems for which one might use a callback in C, introduce some new jargon, and explore how to solve these problems in REALbasic.

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