Special

Introducing the “Welcome to Xojo” Bundle!

New to Xojo and looking for guidance? We've put together a terrific bundle to welcome you! Xojo Bundle

This bundle includes six back issues of the magazine -- all of year 21 in printed book and digital formats -- plus a one-year subscription (beginning with 22.1) so you'll be learning all about Xojo for the next year. It's the perfect way to get started programming with Xojo. And you save as much as $35 over the non-bundle price!

This offer is only available for a limited time as supplies are limited, so hurry today and order this special bundle before the offer goes away!

Article Preview


Buy Now

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.

Notification

...End of Excerpt. Please purchase the magazine to read the full article.