How to call another screen in this code below - c

Question

Good night, I would like some help with this code below, I have to do an exercise that calls another registration screen, the first screen I managed to assemble, make the buttons work too, but I don't find a practical example on the internet to be able to call this one another screen, I've tried in several ways and without success, I would like some help so to be able to call another screen in this code below. I have to call this other screen there on the Register button, you can see that I've already tried and nothing happens.
#define UNICODE
#define _UNICODE
#include <windows.h>
#include <tchar.h>
const TCHAR CLSNAME[] = TEXT("helloworldWClass");
LRESULT CALLBACK winproc(HWND hwnd, UINT wm, WPARAM wp, LPARAM lp);
void addControls(HWND);
int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hInstPrev, PSTR cmdline, int cmdshow)
{
//return MessageBox(NULL, "hello, world", "caption", 0);
WNDCLASSEX wc = { };
MSG msg;
HWND hwnd;
wc.cbSize = sizeof (wc);
wc.style = 0;
wc.lpfnWndProc = winproc;
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
wc.hInstance = hInst;
wc.hIcon = LoadIcon (NULL, IDI_APPLICATION);
wc.hCursor = LoadCursor (NULL, IDC_ARROW);
//wc.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH);
wc.lpszMenuName = NULL;
wc.lpszClassName = CLSNAME;
wc.hIconSm = LoadIcon (NULL, IDI_APPLICATION);
if (!RegisterClassEx(&wc)) {
MessageBox(NULL, TEXT("Could not register window class"),
NULL, MB_ICONERROR);
return 0;
}
hwnd = CreateWindowEx(WS_EX_LEFT,
CLSNAME,
_T("Covid-19"),
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
NULL,
NULL,
hInst,
NULL);
if (!hwnd) {
MessageBox(NULL, TEXT("Could not create window"), NULL, MB_ICONERROR);
return 0;
}
ShowWindow(hwnd, cmdshow);
UpdateWindow(hwnd);
while (GetMessage(&msg, NULL, 0, 0)) {
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return msg.wParam;
}
void addControls(HWND hwnd) {
CreateWindowW(L"Static", L"Login", WS_CHILD | WS_VISIBLE, 600, 0, 100, 18, hwnd, NULL, NULL, NULL);
CreateWindowW(L"Edit", L"", WS_CHILD | WS_VISIBLE, 600, 40, 100, 18, hwnd, NULL, NULL, NULL);
CreateWindowW(L"Static", L"Senha", WS_CHILD | WS_VISIBLE, 600, 80, 100, 18, hwnd, NULL, NULL, NULL);
CreateWindowW(L"Edit", L"", WS_CHILD | WS_VISIBLE, 600, 120, 100, 18, hwnd, NULL, NULL, NULL);
CreateWindowW(L"Button", L"Login", WS_CHILD | WS_VISIBLE, 600, 160, 100, 18, hwnd, (HMENU) 1, NULL, NULL);
CreateWindowW(L"Button", L"Cadastrar", WS_CHILD | WS_VISIBLE, 600, 200, 100, 18, hwnd, (HMENU) 2, NULL, NULL);
}
LRESULT CALLBACK winproc(HWND hwnd, UINT wm, WPARAM wp, LPARAM lp) {
HWND hwndCadastrar;
switch (wm) {
case WM_CREATE:
addControls(hwnd);
break;
case WM_CLOSE:
DestroyWindow(hwnd);
break;
case WM_COMMAND:
if (LOWORD(wp) == 1) {
hwndCadastrar = CreateWindowEx(WS_EX_LEFT,
CLSNAME,
_T("Covid-19 - Cadastrar - Paciente"),
WS_CHILDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
NULL,
NULL,
hwnd,
NULL);
ShowWindow(hwndCadastrar, SW_SHOW);
SetForegroundWindow(hwndCadastrar);
SetFocus(hwndCadastrar);
Window(hwnd);
MessageBox(0, (LPCWSTR)L"Login Efetuado Com Sucesso", (LPCWSTR)L"Login", 0);
} else if (LOWORD(wp) == 2) {
MessageBox(0, (LPCWSTR)L"Cadastro Efetuado Com Sucesso", (LPCWSTR)L"Cadastrar", 0);
}
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
default:
return DefWindowProc(hwnd, wm, wp, lp);
}
}

Answer 1

The child window failed to create.
You cannot pass a HWND to a HINSTANCE parameter.(argument of type HWND is incompatible with parameter of type HINSTANCE)
You cannot create a top-level child window(ERROR_TLW_WITH_WSCHILD).
CW_USEDEFAULT is valid only for overlapped windows; if CW_USEDEFAULT is specified for a pop-up or child window, the nWidth and nHeight parameter are set to zero.
If you want to see the child window caption, add WS_CAPTION.
Finally, the code looks like this:
hwndCadastrar = CreateWindowEx(WS_EX_LEFT,
CLSNAME,
_T("Covid-19 - Cadastrar - Paciente"),
WS_CAPTION |WS_CHILDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
1000,
1000,
hwnd,
NULL,
GetModuleHandle(NULL),
NULL);
For more information about child windows, see Creating, Enumerating, and Sizing Child Windows