C++ WinApp Scroll bar undeclared global variables. - c++

Question

hwnd = CreateWindowEx(
0, // no extended styles
g_szWindowClass, // global string containing name of window class
g_szTitle, // global string containing title bar text
WS_OVERLAPPEDWINDOW |
WS_HSCROLL | WS_VSCROLL, // window styles
CW_USEDEFAULT, // default horizontal position
CW_USEDEFAULT, // default vertical position
CW_USEDEFAULT, // default width
CW_USEDEFAULT, // default height
(HWND) NULL, // no parent for overlapped windows
(HMENU) NULL, // use the window class menu
g_hInst, // global instance handle
(PVOID) NULL // pointer not needed
);
I copied and pasted directly from http://msdn.microsoft.com/en-us/library/windows/desktop/hh298376%28v=vs.85%29.aspx
But, however the variables starting with 'g_' are undefined, how do I define them? I am not finding that info on Microsoft site.
Oh and My Goal is too create a scroll bar. (vertical)
Thanks

Answer 1

g_ indicates a global variable; Declare the 3 variables with a prefix of _g as global. Set
wchar_t g_szClassName[] = L"WindowClassName";
g_szTitle = L"Name"; // use this
g_hInst = thisInstance; // one of mains parameters
So something like this:
// This is unicode.
wchar_t szClassName[] = L"ClassRegisterName";
int WINAPI WinMain (HINSTANCE hThisInstance, HINSTANCE hPrevInstance, LPSTR lpszArgument, int nFunsterStil) {
...
hwnd = CreateWindow(szClassName, L"Your Title", WS_OVERLAPPED | WS_CAPTION | WS_SYSMENU | WS_MINIMIZEBOX | WS_CLIPCHILDREN,
100, 50, 100, 100, NULL, NULL, hThisInstance, NULL);