Drag Initiation From a Container Window

PCONTRECORD  pCRec;
PCNRDRAGINIT pcnrInit;
PDRAGINFO    pDInfo;
DRAGITEM     DItem;
DRAGIMAGE    DImage;

APIRET       rc;
  :
  :
case WM_CONTROL:
     switch (SHORT2FROMMP(mp1))
            {
            case CN_INITDRAG:
                 pcnrInit =                     /* Get container data    */
                    (PCNRDRAGINIT)mp2;
                 pCRec = (PCONTRECORD)pcnrInit->pRecord;

                 if (pCRec == NULL)             /* If no item selected   */
                    return(0);                  /* Return                */

                 pDInfo = DrgAllocDraginfo(1);  /* Allocate DRAGINFO     */

                 DItem.hwndItem = hWnd;         /* Initialize DRAGITEM   */
                 DItem.ulItemID = (ULONG)pCRec;
                 DItem.hstrType =
                    DrgAddStrHandle("DRT_CUSTOMER");
                 DItem.hstrRMF =
                    DrgAddStrHandle("(DRM_SHAREMEM,DRM_PRINT)x(DRF_TEXT)");
                 DItem.fsControl = 0;
                 DItem.fsSupportedOps = DO_COPYABLE | DO_MOVEABLE;

                 rc = DrgSetDragItem(pDInfo,    /* Set item in DRAGINFO  */
                         &DItem,                /* Pointer to DRAGITEM   */
                         sizeof(DItem),         /* Size of DRAGITEM      */
                         0);                    /* Index of DRAGITEM     */

                 DImage.cb = sizeof(DRAGIMAGE); /* Initialize DRAGIMAGE  */
                 DImage.cptl = 0;               /* Not a polygon         */
                 DImage.hImage = hPostIcon;     /* Icon handle for drag  */
                 DImage.fl = DRG_ICON;          /* Dragging an icon      */
                 DImage.cxOffset = 0;           /* No hotspot            */
                 DImage.cyOffset = 0;

                 hDrop = DrgDrag(hWnd,          /* Initiate drag         */
                            pDInfo,             /* DRAGINFO structure    */
                            (PDRAGIMAGE)&DImage, /* DRAGIMAGE structure  */
                            1,                  /* Only one DRAGIMAGE    */
                            VK_ENDDRAG,         /* End of drag indicator */
                            NULL);              /* Reserved              */

                 DrgFreeDragInfo(pDInfo);       /* Free DRAGINFO struct  */
                 break;

Another window class would perform these operations in response to a WM_BEGINDRAG message, rather than a WM_CONTROL message with the CN_INITDRAG indicator.