Download Source Code and Example
The Windows
Control Panel
is the ideal way to allow a user to alter settings for an application
that runs
in the background, or automatically. But what are control panel
applets
and how do you write one? Well, after some exploring in the MSDN I
discovered
that control panel applets are just standard DLLs with a particular set
of entry
points and a .cpl extension. Place such a file in the Windows System
directory
and the next time you start up control panel your applet will be there.
Having
discovered what I needed to know I set about writing a control panel
applet and
once I’d done that, I turned the bulk of the code into a mini applet
framework
so I wouldn’t have to write it ever again!
To implement your control panel applet
all you
need to do is the following:
- include
"ControlApplet.hpp" and
publicly derive a class from CJBControlPanelApplet.
- call the CJBControlPanelApplet
constructor
and pass resource IDs for the applet’s icon, name and
description.
- implement the pure virtual
function
OnDoubleClick() – this is where your applet becomes live and can
display a
dialog or whatever.
- create an instance of your applet
class at
global scope.
- link with ControlApplet.cpp and
include
ControlApplet.def in your project. ControlApplet.cpp gives you the
implementation of CJBControlPanelApplet and suitable DllMain() and
CPlApplet() DLL entry point functions.
So that this article and code can be kept up to date more easily
I’ve
provided a link to where the article is located on my own web pages. Read
the full article and download the source code.
Last updated: 27 June 1998
