LFile::LoadOffset

class LUserFile : public LFile 
{ 
   public: 
      LUserFile (); 
      virtual ~LUserFile (); 
      virtual L_INT LoadFileOffsetCallBack(pFILEINFO pFileInfo, 
      LBitmapBase * pLBitmap, 
      LBuffer * pLBuffer, 
      L_UINT uFlags, 
      L_INT nRow, 
      L_INT nLines); 
      virtual L_INT SaveFileOffsetCallBack(LBitmapBase * pLBitmap, 
             LBuffer * pLBuffer, 
             L_UINT uRow, 
             L_UINT uLines); 
}; 
 
LUserFile::LUserFile () 
{ 
} 
 
LUserFile::~LUserFile () 
{ 
} 
 
L_INT LUserFile::LoadFileOffsetCallBack(pFILEINFO pFileInfo, 
                                       LBitmapBase * pLBitmap, 
                                       LBuffer * pLBuffer, 
                                       L_UINT uFlags, 
                                       L_INT nRow, 
                                       L_INT nLines) 
{ 
   UNREFERENCED_PARAMETER(pFileInfo); 
 
   UNREFERENCED_PARAMETER(pLBitmap); 
 
   UNREFERENCED_PARAMETER(pLBuffer); 
 
   UNREFERENCED_PARAMETER(uFlags); 
 
   UNREFERENCED_PARAMETER(nRow); 
 
   UNREFERENCED_PARAMETER(nLines); 
 
   MessageBox(NULL,TEXT("Here the user can set his code for LoadOffset"), 
   TEXT("LoadOffset"),MB_OK); 
   return SUCCESS ; 
} 
 
L_INT LUserFile:: SaveFileOffsetCallBack(LBitmapBase * pLBitmap, 
                                         LBuffer * pLBuffer, 
                                         L_UINT uRow, 
                                         L_UINT uLines) 
{ 
   UNREFERENCED_PARAMETER(pLBitmap); 
 
   UNREFERENCED_PARAMETER(pLBuffer); 
 
   UNREFERENCED_PARAMETER(uRow); 
 
   UNREFERENCED_PARAMETER(uLines); 
 
   MessageBox(NULL,TEXT("Here the user can set his code for SaveOffset"), 
   TEXT("SaveOffset"),MB_OK); 
   return SUCCESS ; 
} 
 
L_INT LFile__LoadOffsetExample(LBitmapBase& LeadBitmap,HWND hWnd) 
{ 
   L_INT nRet; // Return value  
   L_TCHAR szMessage[80]; // Buffer for the MessageBox string 
   L_HANDLE OffsetFile; // File handle  
   L_OFFSET SizeWritten; // Variable to be updated with the size written  
   LUserFile UserLeadFile ; 
   DWORD wWriteBytes; 
 
   UserLeadFile.SetBitmap(&LeadBitmap); 
   // Create a file  
 
   OffsetFile = CreateFile(MAKE_IMAGE_PATH(TEXT("TOFFSET.TST")), GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0); 
 
   // Write some text in the file -- 29 characters and a terminator  
   WriteFile(OffsetFile, TEXT("This is a 29-character string"), 30, &wWriteBytes, NULL); 
 
   // Save the image file with an offset inside the TOFFSET.TST file  
   nRet = UserLeadFile.SaveOffset((L_HFILE)OffsetFile, 30, &SizeWritten, FILE_BMP, 8, 0, SAVEFILE_FIXEDPALETTE, NULL); 
   if(nRet != SUCCESS) 
      return nRet; 
 
   // Close the file  
   CloseHandle(OffsetFile); 
 
   // Notify the user with a message box  
   if (nRet == SUCCESS) 
   { 
      MessageBox (hWnd, TEXT("File was saved"), TEXT("Notice"), MB_OK); 
   } 
   else 
   { 
      wsprintf (szMessage, TEXT("Error %d saving the file"), nRet); 
      MessageBox (hWnd, szMessage, TEXT("Error"), MB_OK); 
      return nRet; 
   } 
 
 
   // Free the bitmap  
   LeadBitmap.Free(); 
 
   /***** Now load the file we just saved ****/ 
   /* Open the file and get the file handle **/ 
 
   OffsetFile = CreateFile(MAKE_IMAGE_PATH(TEXT("TOFFSET.TST")), GENERIC_ALL, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0); 
 
   // Load the file with a 30-byte offset 
   nRet = UserLeadFile.LoadOffset((L_HFILE) OffsetFile, 30, SizeWritten, 
                                  0, ORDER_BGR, LOADFILE_ALLOCATE | LOADFILE_STORE, NULL); 
 
   // Close the file  
   CloseHandle(OffsetFile); 
 
   /* Notify the user with a message box. The BPS in the message confirms that it is a new image. */ 
   if (nRet == SUCCESS) 
   { 
      wsprintf (szMessage, TEXT("New file loaded at %d BPS"), LeadBitmap.GetBitsPerPixel()); 
      MessageBox (NULL, szMessage, TEXT("Notice"), MB_OK); 
   } 
   else 
   { 
      wsprintf (szMessage, TEXT("Error %d loading the file"), nRet); 
      MessageBox (NULL, szMessage, TEXT("Error"), MB_OK); 
   } 
 
   return SUCCESS; 
}