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LWia::IsAvailable

Summary

Determines whether a WIA source is installed.

Syntax

#include "ltwrappr.h"

virtual L_BOOL LWia::IsAvailable(uWiaVersion)

Parameters

L_UINT uWiaVersion

The WIA version to be used. Possible values are:

Value	Meaning
WiaVersion1	[1] Use WIA version 1.
WiaVersion2	[2] Use WIA version 2.

Returns

Value	Meaning
TRUE	At least one WIA source is installed.
FALSE	No WIA source is installed.

Comments

This feature is available in LEADTOOLS version 16 or higher.

Use this function when deciding whether to enable or disable WIA menu items.

Required DLLs and Libraries

LTWIA
For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Platforms

Earlier and later operating systems than Windows XP for WIA Version 1.

Windows VISTA or later for WIA Version 2.

Example

class CMyWIA : public LWia 
{ 
public: 
   L_INT AcquireCallBack(pBITMAPHANDLE pBitmap, L_TCHAR * pszFilename, L_UINT32 uPercent, L_UINT32 uFlags); 
}; 
 
L_INT CMyWIA::AcquireCallBack(pBITMAPHANDLE pBitmap, L_TCHAR * pszFilename, L_UINT32 uPercent, L_UINT32 uFlags) 
{ 
   UNREFERENCED_PARAMETER(pBitmap); 
   UNREFERENCED_PARAMETER(pszFilename); 
   UNREFERENCED_PARAMETER(uPercent); 
   UNREFERENCED_PARAMETER(uFlags); 
 
   // You can do here any processing to the bitmap 
 
   return WIA_SUCCESS; 
} 
 
L_INT LWIA__IsAvailableExample(L_UINT uWiaVersion) 
{ 
   CMyWIA               MyClass; 
   LWIAACQUIREOPTIONS   AcquireOpts; 
   L_BOOL               bAvailable; 
   L_INT                nRet; 
 
   /* Check to see if user passed WIA version is installed */ 
   bAvailable = MyClass.IsAvailable(uWiaVersion); 
   if (bAvailable) 
   { 
      nRet = MyClass.InitSession(uWiaVersion); 
      if (nRet != SUCCESS) 
         return nRet; 
 
      nRet = MyClass.SelectDeviceDlg(WiaDeviceTypeDefault, L_WIA_SELECT_DEVICE_NODEFAULT); 
      if (nRet != SUCCESS) 
         return nRet; 
 
      /* Initialize and fill the required fields from the LWIAACQUIREOPTIONS structure */ 
      memset(&AcquireOpts, 0, sizeof(LWIAACQUIREOPTIONS)); 
      AcquireOpts.uStructSize = sizeof(LWIAACQUIREOPTIONS); 
      AcquireOpts.uMemBufSize = 64 * 1024; 
      AcquireOpts.bDoubleBuffer = TRUE; 
 
      MyClass.EnableCallBack (TRUE); 
 
      nRet = MyClass.Acquire(L_WIA_DEVICE_DIALOG_USE_COMMON_UI,  
                             &AcquireOpts,  
                             NULL,  
                             NULL,  
                             NULL); 
      if (nRet != SUCCESS) 
         return nRet; 
 
      nRet = MyClass.EndSession(); 
      if (nRet != SUCCESS) 
         return nRet; 
   } 
 
   return SUCCESS; 
}