I have this problem with a callback with dialog boxes... I want to make a class giving basic functionality using the DialogBox/CreateDialog functions, but the callback function is a problem, as I don't know how to access my original class from it. Creating a global value just defeats the purpose of having it in a class, and there are no user defined parameters I can pass into the DialogBox/CreateDialog functions for use in the callback function (so no pointer passing). And just using mfc is out because I want to use seperate resources from my dlls (which mfc, as far as I can figure out, spits the dummy over (AfxSetResourceHandle sets the resource for the entire program)) At the moment it is like this...

int CMyDialog::DoModal() { DialogBox(hInst,MAKEINTRESOURCE(DialogRef),AfxGetMainWnd()->GetSafeHwnd(),DialogProc); return 0; } INT_PTR CMyDialog::DialogProc(HWND hWndDlg,UINT uMsg,WPARAM wParam,LPARAM lParam) { switch(uMsg) { case WM_CLOSE: EndDialog(hWndDlg,0); break; }; return FALSE; };

where DialogProc is static, but I want to get at the CMyDialog class that created the hWnd... This is really pissing me off. Any ideas? btw, I'm not going to be able to reply for a while... Edited by - ludemann8 on March 5, 2001 2:34:25 PM

Here is a simple idea, hope it what you need.
When you call your callback function from you class pass this to it, now you've got a pointer to you dialog class.
I just noticed that you callback function is part of you dialog class so you don't need to pass this to it, its already available.


Edited by - xstreme2000 on March 5, 2001 3:43:44 PM

Here''s how it''s usually done:

int CMyDialog::DoModal(){ DialogBoxParam(hInst,MAKEINTRESOURCE(DialogRef),AfxGetMainWnd()->GetSafeHwnd(),DialogProc, (int)this); return 0;}INT_PTR CMyDialog::DialogProc(HWND hWndDlg,UINT uMsg,WPARAM wParam,LPARAM lParam){ CMyDialog* _this; _this = (CMyDialog*)GetWindowLong( hWndDlg, GWL_USERDATA ); if( _this == NULL ) return FALSE; switch(uMsg) { case WM_INITDIALOG: SetWindowLong( hWndDlg, GWL_USERDATA, lParam ); break; case WM_CLOSE: EndDialog(hWndDlg,0); break; case WM_COMMAND: _this->OnCommand(); break; }; return FALSE;};

Cheers!
Meduzza

Thanks for the replies,

xstreme2000, that is no good as the callback function type is already defined.
Meduzza, thanks very much... I had a look and found that DialogBox is just a redifinition of DialogBoxParam. Thanks.

Edited by - ludemann8 on March 6, 2001 7:53:32 AM

Edited by - ludemann8 on March 6, 2001 7:55:52 AM