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Issue 3.6

COLUMN

Implementing a MessageCenter Module

Decoupling The Observer Pattern

Issue: 3.6 (July/August 2005)
Author: Charles Yeomans
Author Bio: Charles Yeomans is a software developer in Lexington, Kentucky.
Article Description: No description available.
Article Length (in bytes): 5,350
Starting Page Number: 35
Article Number: 3616
Related Link(s): None

Excerpt of article text...

Your application allows users to customize its user interface and other behavior. A user can change the font, change colors, load different skins, and so forth. This means that many controls and objects need to know when settings are changed.

A standard solution to such a problem is described by the Observer pattern. In this pattern, objects that wish to be notified of some change to an object's state register their interest with the object. This object then notifies observers when a change occurs.

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