ImageGear for C and C++ on Linux v18.8 - Updated
IG_mpi_CB_get
API Reference Guide > Core Component API Reference > Core Component Functions Reference > Multi Page Image Functions > IG_mpi_CB_get

This function returns information about the associated private data pointer and update function using the dwCBID identifier.

Declaration:

 
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AT_ERRCOUNT ACCUAPI IG_mpi_CB_get( 
        [IN] HMIGEAR hMIGear, 
        [IN] DWORD dwCBID, 
        [OUT] LPVOID FAR* lplpPrivate,
        [OUT] LPFNIG_MPCB_UPDATE FAR* lplpfnUpdate
);

Arguments:

Name Type Description
hMIGear HMIGEAR The handle of the allocated multi-page image.
dwCBID DWORD A unique identifier of the private data and function.
lplpPrivate LPVOID FAR* A pointer indicating where to receive the private data.
lplpfnUpdate LPFNIG_MPCB_UPDATE FAR* A pointer indicating where to receive the update function.

Return Value:

Returns the number of ImageGear errors that occurred during this function call. If there are no errors, the return value is IGE_SUCCESS.

Supported Raster Image Formats:

All pixel formats supported by ImageGear for C and C++.

Example:

 
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HMIGEAR          hMIGear;    /* handle to multi-page image */
AT_ERRCOUNT nErrCount = IGE_SUCCESS; /* will hold returned error count */
LPVOID lpData;
LPFNIG_MPCB_UPDATE        lpUpdateFunc;
DWORD dwCBID;
 ...
nErrCount = IG_mpi_CB_set( hMIGear, (LPVOID)hMIGear, _MPWndUpdate, &dwCBID );
 ...
nErrCount = IG_mpi_CB_get( hMIGear, dwCBID, &lpData, &lpUpdateFunc );
 ...
VOID  ACCUAPI  _MPWndUpdate(
   DWORD          dwCBID,
   LPVOID         lpPrivate,     /* Private data passed in */
   AT_MODE        nMode,
   UINT           nPage,
   UINT           nCount
)
{
   switch( nMode )
   {
   case  IG_MPCBMODE_MPI_DELETE:
         ...
      break;
   case  IG_MPCBMODE_MPI_ASSOCIATED:
         ...
      break;
   case  IG_MPCBMODE_MPI_CLOSE:
         ...
      break;
         ...
   }
}

Remarks:

See the IG_mpi_CB_set() documentation for a description of how notification works with multi-page images.

If there is no association with an external file, then NULL values are assigned to both pointers.