Hi guys I have an issue with this procedure: HWND Container::createWindow(void)

Question

Hi guys I have an issue with this procedure: HWND Container::createWindow(void)

const {
int width = CLASSNAME_APP_MIN_WIDTH;
int height = CLASSNAME_APP_MIN_HEIGHT;

auto parentHandle = this->getParent()->getHWND();
auto hInstance = this->getInstance();

return ::CreateWindow(
_T(CLASSNAME_CONTAINER),
nullptr,
WS_CHILD,
0, 0,
width, height,
parentHandle,
nullptr,
hInstance,
nullptr
);
}

The debugger says that CreateWindowW is trying to call a null pointer to a function deep inside user32.dll

I guess some of the parameters are wrong.

I know for sure that:
1. parentHandle comes from the hwnd parameter of WM_CREATE
2. hInstance is valid
3. the other nullptr s are not the issue.

What would you suggest?