winapi full screen leaves 3 tickles - c

Question

here is a code I found here :
https://www.codeproject.com/Questions/108400/How-to-Set-Win32-Application-to-Full-Screen-C
. I had a little problem with it. In part 1 it queries the window style and then in the second 2 part it defines styles that we will remove in part 3. then in part 4 leaves three butts on two sides and bottom. what can i do?
//move to full screen
//1
DWORD dwStyle = ::GetWindowLong(hwnd, GWL_STYLE);
//2
DWORD dwRemove = WS_CAPTION | WS_SYSMENU | WS_MINIMIZEBOX | WS_MAXIMIZEBOX;
//3
DWORD dwNewStyle = dwStyle & ~dwRemove;
::SetWindowLong(hwnd, GWL_STYLE, dwNewStyle);
//4
::SetWindowPos(hwnd, NULL, 0, 0, ::GetDeviceCaps(hdc, HORZRES), ::GetDeviceCaps(hdc, VERTRES),SWP_FRAMECHANGED);

Answer 1

Raymond Chen gave the correct way to do this in his blog: How do I switch a window between normal and fullscreen?：
Here is the sample that you can refer to :
#include <Windows.h>
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
WINDOWPLACEMENT g_wpPrev = { sizeof(g_wpPrev) };
void setFullWindow(HWND hwnd)
{
DWORD dwStyle = GetWindowLong(hwnd, GWL_STYLE);
if (dwStyle & WS_OVERLAPPEDWINDOW) {
MONITORINFO mi = { sizeof(mi) };
if (GetWindowPlacement(hwnd, &g_wpPrev) &&
GetMonitorInfo(MonitorFromWindow(hwnd,
MONITOR_DEFAULTTOPRIMARY), &mi)) {
SetWindowLong(hwnd, GWL_STYLE,
dwStyle & ~WS_OVERLAPPEDWINDOW);
SetWindowPos(hwnd, HWND_TOP,
mi.rcMonitor.left, mi.rcMonitor.top,
mi.rcMonitor.right - mi.rcMonitor.left,
mi.rcMonitor.bottom - mi.rcMonitor.top,
SWP_NOOWNERZORDER | SWP_FRAMECHANGED);
}
}
else {
SetWindowLong(hwnd, GWL_STYLE,
dwStyle | WS_OVERLAPPEDWINDOW);
SetWindowPlacement(hwnd, &g_wpPrev);
SetWindowPos(hwnd, NULL, 0, 0, 0, 0,
SWP_NOMOVE | SWP_NOSIZE | SWP_NOZORDER |
SWP_NOOWNERZORDER | SWP_FRAMECHANGED);
}
}
int WINAPI WinMain(_In_ HINSTANCE hInstance, _In_opt_ HINSTANCE hPrevInstance, _In_ LPSTR szCmdLine, _In_ int iCmdShow)
{
static TCHAR szAppName[] = TEXT("hello windows");
HWND hwnd;
MSG msg;
WNDCLASS wndclass;
wndclass.style = CS_HREDRAW | CS_VREDRAW;
wndclass.lpfnWndProc = WndProc;
wndclass.cbClsExtra = 0;
wndclass.cbWndExtra = 0;
wndclass.hInstance = hInstance;
wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
wndclass.lpszMenuName = NULL;
wndclass.lpszClassName = szAppName;
if (!RegisterClass(&wndclass))
{
MessageBox(NULL, TEXT("This program requires Windows NT!"), szAppName, MB_ICONERROR);
}
hwnd = CreateWindow(szAppName,
TEXT("the hello program"),
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
NULL,
NULL,
hInstance,
NULL);
setFullWindow(hwnd);
ShowWindow(hwnd, iCmdShow);
UpdateWindow(hwnd);
while (GetMessageW(&msg, NULL, 0, 0))
{
TranslateMessage(&msg);
DispatchMessageW(&msg);
}
return msg.wParam;
}
LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message)
{
case WM_DESTROY:
PostQuitMessage(0);
return 0;
}
return DefWindowProc(hwnd, message, wParam, lParam);
}