Note: The purpose of this WIA tutorial is to provide you a quick and easy way to enumerate WIA devices. For more in-depth WIA programming, refer to the WIA demo.
To enumerate the WIA devices installed on your machine:
1. |
Create a new directory in the \Examples\CDLL directory called WiaTutorial. |
2. |
Copy everything in the SimpleLoad directory into the WiaTutorial directory. |
3. |
Compile the project as it is and run SimpleLoad.exe to familiarize yourself with the basic program. |
4. |
In the Imports.cpp, add the following lines: |
#if defined(WIN64)
#pragma comment(lib, "..\\..\\..\\Lib"L_VER_DESIGNATOR"\\CDLL\\x64\\Ltwia_x.lib")
#else
#pragma comment(lib, "..\\..\\..\\Lib"L_VER_DESIGNATOR"\\CDLL\\Win32\\Ltwia_u.lib")
#endif // #if defined(WIN64)
5. |
Add the following line in StdAfx.h in the WiaTutorial directory: |
#include "..\..\..\include\ltwia.h"
6. |
Define the following global variable in Ezfunc.h in the WiaTutorial directory: |
HWIASESSION hSession = NULL;
Also, add the following defines:
#define IDM_ENUMERATE_WIA_DEVICES 200
7. |
Edit EZFUNC.RC file in the WiaTutorial directory and add the following lines: |
#include "EZFUNC.H"
MAIN_MENU MENU
BEGIN
MENUITEM "Enumerate WIA Devices" IDM_ENUMERATE_WIA_DEVICES
END
8. |
In the InitApplication function change the line: |
wcWindowClass.lpszMenuName = NULL; /* No menu */
to be
wcWindowClass.lpszMenuName = TEXT("MAIN_MENU");
9. |
In the MainWndProc function and before the handling of the WM_PALETTECHANGED message add the following code: |
case WM_COMMAND:
{
switch (LOWORD(wParam))
{
case IDM_ENUMERATE_WIA_DEVICES:
{
}
break;
}
}
break;
10. |
In the WM_CREATE message handler add the following code at the end of it (after SendMessage (hWnd, WM_QUERYNEWPALETTE, 0, 0L);): |
nRet = L_WiaInitSession(WiaVersion1, &hSession);
if (nRet != WIA_SUCCESS)
return FALSE;
11. |
In the WM_DESTROY message handler add the following code at the end of it (before the PostQuitMessage (0);): |
L_WiaEndSession(hSession);
12. |
In the IDM_ENUMERATE_WIA_DEVICES menu handler add the following code: |
case IDM_ENUMERATE_WIA_DEVICES:
{
nRet = L_WiaEnumDevices(hSession, WiaEnumDevicesCB, NULL);
if (nRet != WIA_SUCCESS)
return FALSE;
}
break;
13. |
In Ezfunc.cpp file, add the following function before MainWndProc function: |
L_INT CALLBACK WiaEnumDevicesCB(HWIASESSION hSession, pLWIADEVICEID pDeviceID, L_VOID * pUserData)
{
UNREFERENCED_PARAMETER(hSession);
UNREFERENCED_PARAMETER(pUserData);
L_TCHAR szDeviceInfo[MAX_PATH] = TEXT("");
wsprintf(szDeviceInfo,
TEXT("Device ID: %s\nDevice Name: %s\nDevice Desc.:%s"),
pDeviceID->pszDeviceId,
pDeviceID->pszDeviceName,
pDeviceID->pszDeviceDesc);
MessageBox(NULL,
szDeviceInfo,
TEXT("Available WIA Devices"),
MB_OK | MB_ICONINFORMATION);
return WIA_SUCCESS;
}
14. |
Compile and test the program. |