DrgReallocDragInfo - Example Code

This example uses DrgReallocDragInfo to reallocate the DRAGINFO structure when an object is picked up or added to the lazy drag set. It checks whether a lazy drag operation is already in progress, and if so, adds one to the number of objects currently being dragged and calls DrgReallocDragInfo to obtain a new DRAGINFO structure with the required number of DRAGITEM structures.

#define  INCL_WINSTDDRAG
#include <os2.h>

PDRAGINFO  pdinfoCurrent;   /* Pointer to the current DRAGINFO     */
PDRAGINFO  pdinfoOld;       /* Pointer to the DRAGINFO to be freed */
ULONG      cditem;          /* Number of DRAGITEMS                 */
  .
  .
  .
case WM_PICKUP:

   if (DrgQueryDragStatus() & DGS_LAZYDRAGINPROGRESS)
   {
      /* Get a pinter to the current DRAGINFO structure */
      pdinfoOld=DrgQueryDraginfoPtr(NULL);

      /* Add space for one more DRAGITEM */
      cditem=pdinfoOld->cditem+1;

      /* Reallocate the DRAGINFO */
      pdinfoCurrent=DrgReallocDraginfo(pdinfoOld, cditem);
      if(pdinfoCurrent)
      {
         /* Continue the lazy drag operation */
         DrgLazyDrag( ... )
      }
   }