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identifiying/keeping appart multiple instances of dialog boxes


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so i have been messing with native GUI programming in msvs2008 recently and lots and lots of problems & questions arose... :)

Most of them were exterminated by a quick google search. :)

This one is a little persistent, though:

I have a class, myclass. The user can create multiple instances of that class.

Every class instance has its own instance of a dialog box, which can be displayed at the same time.

How can i now link a class instance to a dialog box?

ie, if the dialog boxes CALLBACK routine is called, how can i know which class instances dialog box send the message?

deep0 :)

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I don't think I've understood your problem well, but what if you associate a value with each dialogbox handle using SetWindowLong and DWL_USER as parameter after the creation of the dialogbox :

I think of something like (as I don't know your C++ class implementation):

HWND myclass::Create(..){
this->hwnd = CreateDialogParam(...);
void myclass::SetID(DWORD id){
SetWindowLong(this->hwnd, DWL_USER, id);
myclass *mc = new myclass(...);
mc->SetID(0xFEADBEEF);...myclass *mc2 = new myclass(...);

and in the callback function, you can use a switch/case to test against the already known IDs after calling

Edited by Zool@nder
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