GroupBox.cpp

#pragma comment(linker,"\"/manifestdependency:type='win32' name='Microsoft.Windows.Common-Controls' version='6.0.0.0' processorArchitecture='*' publicKeyToken='6595b64144ccf1df' language='*'\"")

#include <string>
#include <Windows.h>
#include <CommCtrl.h>

HWND window = nullptr;
HWND groupBox1 = nullptr;
HWND groupBox2 = nullptr;
WNDPROC defWndProc = nullptr;

LRESULT OnWindowClose(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) {
  PostQuitMessage(0);
  return CallWindowProc(defWndProc, hwnd, message, wParam, lParam);
}

LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) {
  if (message == WM_CLOSE && hwnd == window) return OnWindowClose(hwnd, message, wParam, lParam);
  return CallWindowProc(defWndProc, hwnd, message, wParam, lParam);
}

int main() {
  window = CreateWindowEx(0, WC_DIALOG, L"GroupBox example", WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 656, 521, nullptr, nullptr, nullptr, nullptr);
  groupBox1 = CreateWindowEx(0, WC_BUTTON, L"GroupBox 1", WS_CHILD | WS_VISIBLE | BS_GROUPBOX, 10, 10, 305, 460, window, nullptr, nullptr, nullptr);
  groupBox2 = CreateWindowEx(0, WC_BUTTON, L"", WS_CHILD | WS_VISIBLE | BS_GROUPBOX, 325, 10, 305, 460, window, nullptr, nullptr, nullptr);

  defWndProc = reinterpret_cast<WNDPROC>(SetWindowLongPtr(window, GWLP_WNDPROC, reinterpret_cast<LONG_PTR>(WndProc)));
  ShowWindow(window, SW_SHOW);

  MSG message = { 0 };
  while (GetMessage(&message, nullptr, 0, 0))
    DispatchMessage(&message);
}