🚀 go-pugleaf

"SubZero" <g_ates@hotmail.com> wrote:

>I have a program that I want it to act like Outlook Express in the sense 
>that when the program is minimized or in the tray, and when user clicks on 
>the desktop icon, instead of relaunching a second instance, it should bring 
>the first instance to screen (window should be visible).

A possibility.

When your program starts, use RegisterWindowMessage() to generate a
special unique-to-you Windows message ID.

Then attempt to create a mutex. If it is created successfully, then
you're the original copy, so run as normal. (Don't forget to release it
at the end.)

If you failed, you're the copy. So use EnumWindows to find all top-level
windows in turn, and send the message to each of them. And then
terminate. Or send it to HWND_BROADCAST (simpler).

Meanwhile, when the original receives the message, it knows that it
should pop up and show itself.

Note - I've not explicitly done this.

Alan Bellingham
-- 
ACCU Conference 2005 - 20-23 April, Randolph Hotel, Oxford, UK