DrgSetDragImage

This function sets the image that is being dragged.

Syntax

DrgSetDragImage(pdinfo, pdimg, cdimg, pRsvd)

Parameters

pdinfo (PDRAGINFO) - input

Pointer to the DRAGINFO structure representing the drag operation for which the pointer is to be set.

pdimg (PDRAGIMAGE) - input

Pointer to an array of DRAGIMAGE structures.

These structures describe the images to be drawn under the pointer during the drag.

cdimg (ULONG) - input

Number of DRAGIMAGE structures in the pdimg array.

pRsvd (PVOID) - input

Reserved value, must be NULL.

Returns

rc (BOOL) - returns

Success indicator.

TRUE - Successful completion.

FALSE - Error occurred.

Remarks

The image that is set with DrgSetDragImage is used only while the pointer is over the target that made the call. If the pointer leaves the original target, the new target can specify an image by calling DrgSetDragImage. If the new target does not call DrgSetDragImage, the original image that was supplied on the call to DrgDrag is used.

Errors

Possible returns from WinGetLastError:

PMERR_ACCESS_DENIED (0x150D)

The memory block was not allocated properly.

PMERR_INVALID_PARAMETERS (0x1208)

An application parameter value is invalid for its converted PM type. For example: a 4-byte value outside the range -32 768 to +32 767 cannot be converted to a SHORT, and a negative number cannot be converted to a ULONG or USHORT.

PMERR_INSUFFICIENT_MEMORY (0x203E)

The operation terminated through insufficient memory.

Example Code

This example sets the icon image that is displayed during a direct manipulation operation.

#define INCL_GPIBITMAPS /* GPI Bit Map Functions                */
#define INCL_WINSTDDRAG /* Direct Manipulation (Drag) Functions */
#include <os2.h>

#define ID_BITMAP 257 /* .rc file: "bitmap 257 drgimage.bmp" */

HPS       hps;       /* Presentation space handle            */
BOOL      flResult;
HAB       hab;
PDRAGINFO pdinfo;
DRAGIMAGE dimg;
HBITMAP   hbm;       /* Bit-map handle                     */
HWND      hwnd;

/*****************************************************************/
/* Load a bit map for use as a drag image                      */
/*****************************************************************/
case WM_CREATE:
   hps = WinGetPS(hwnd);
   hbm = GpiLoadBitmap(hps,0L,ID_BITMAP,20L,20L);
   WinReleasePS(hps);
   break;

case DM_DRAGOVER:
   /*****************************************************************/
   /* Initialize the DRAGIMAGE structure                           */
   /*****************************************************************/
   dimg.cb = sizeof(DRAGIMAGE);          /* Size control block         */
   dimg.cptl = 0;
   dimg.hImage = hbm;                    /* Image handle passed to     */
                                        /* DrgDrag                    */
   dimg.sizlStretch.cx = 20L;             /* Size to stretch ico or    */
   dimg.sizlStretch.cy = 20L;             /* bmp to                     */
   dimg.fl = DRG_BITMAP |
             DRG_STRETCH;               /* Stretch to size specified  */
   dimg.cxOffset = 0;                    /* Offset of the origin of    */
   dimg.cyOffset = 0;                    /* the image from the pointer */
                                        /* hotspot                    */
   /*****************************************************************/
   /* Set the drag image                                          */
   /*****************************************************************/
   flResult= DrgSetDragImage(pdinfo,&dimg,(ULONG)sizeof(dimg), NULL);

Related Functions

• DrgSetDragPointer