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L_TwainCreateNumericContainerRange

Summary

Allocates the hContainer member of the TW_CAPABILITY structure to be type TW_RANGE and fills it with the appropriate data.

Syntax

#include "lttwn.h"

L_LTTWN_API L_INT L_TwainCreateNumericContainerRange (pCapability, Type, uMinValue, uMaxValue, uStepSize, uDefaultValue, uCurrentValue)

Parameters

TW_CAPABILITY * pCapability

Pointer to a structure that contains the capability container to allocate as type TW_RANGE.

LTWAINNUMERICTYPE Type

Type of data contained in the TW_RANGE container. For a list of possible values, refer to LTWAINNUMERICTYPE.

L_UINT32 uMinValue

The minimum value of the range.

L_UINT32 uMaxValue

The maximum value of the range.

L_UINT32 uStepSize

The step size value of the range.

L_UINT32 uDefaultValue

The default value of the range.

L_UINT32 uCurrentValue

The current value of the range.

Returns

Value	Meaning
SUCCESS	The function was successful.
! = SUCCESS	An error occurred. Refer to Return Codes.

Comments

When enumerating and getting capabilities, the toolkit takes care of creating the necessary TW_CAPABILITY containers. However, if the user wants to set a capability using the L_TwainSetCapability function, he or she must declare a TW_CAPABILITY container of the appropriate type (TW_ARRAY, TW_ENUMERATION, TW_RANGE, or TW_ONEVALUE).

The step size is the amount of increase from one step to the next within the range uMinVal to uMaxVal. For example, if uMinValue = 0, uMaxValue = 100, and uStepSize = 2, then it will take 50 steps to increase from 0 to 100.

Required DLLs and Libraries

LTTWN
For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files to be Included with your Application.

Example

L_INT TwainCreateNumericContainerRangeExample(HTWAINSESSION g_hSession) 
{ 
   L_INT nRet; 
   TW_CAPABILITY twCap; 
 
   memset (&twCap, 0, sizeof(TW_CAPABILITY)); 
   twCap.Cap = ICAP_XRESOLUTION; 
   twCap.ConType = TWON_RANGE; 
 
   nRet = L_TwainCreateNumericContainerRange(&twCap, TWAINNUMERICTYPE_TW_FIX32, 100, 600, 100, 200, 300); 
   if(nRet != SUCCESS) 
      return nRet; 
   nRet = L_TwainStartCapsNeg(g_hSession); 
   if(nRet != SUCCESS) 
      return nRet; 
   nRet = L_TwainSetCapability(g_hSession, &twCap, LTWAIN_CAPABILITY_SET); 
   if(nRet != SUCCESS) 
      return nRet; 
   nRet = L_TwainFreeContainer(&twCap); 
   if(nRet != SUCCESS) 
      return nRet; 
   nRet = L_TwainEndCapsNeg(g_hSession); 
   if(nRet != SUCCESS) 
      return nRet; 
   return SUCCESS; 
}