I have a picture control in a dialog form and I use
CWnd *pWnd = (CWnd*)GetDlgItem(IDC_GRAPH_FRAME);
CDC *pDC = pWnd->GetDC ();

to get pDC and use it draw some lines on the picture. However, it seems the picture control does not update it automatically. So, if I have another window to cover the dialog form, after I move the window, the picture on dialog form will NOT refresh itself. If the project has doc/view, I can use OnDraw(). It is a dialog based form, What I should I?


thanks