代码来源 :http://www.arch-pub.com/problem-about-CPropertyPage_10682271.html
CWnd* pAcadWnd = CWnd::FromHandle(adsw_acadMainWnd());
// or use acedGet... to retrieve a handle to the main CAD window
pAcadWnd->EnableWindow(TRUE);
ShowWindow(SW_HIDE); // this hides your dialog
pAcadWnd->SetFocus();
(hail to Charles McAuley's great book on ARX for CAD2k!)