Windows-API-examples/firststeps/flashing.c

#include <windows.h>

LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);


int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
                    PWSTR lpCmdLine, int nCmdShow) {
    MSG  msg;    
    WNDCLASSW wc = {0};
    wc.lpszClassName = L"Flash";
    wc.hInstance     = hInstance;
    wc.hbrBackground = GetSysColorBrush(COLOR_3DFACE);
    wc.lpfnWndProc   = WndProc;
    wc.hCursor       = LoadCursor(0,IDC_ARROW);

    RegisterClassW(&wc);
    CreateWindowW(wc.lpszClassName, L"Flash",
                 WS_OVERLAPPEDWINDOW | WS_VISIBLE,
                 100, 100, 250, 180, 0, 0, hInstance, 0);

    while(GetMessage(&msg, NULL, 0, 0)) {
    
      TranslateMessage(&msg);
      DispatchMessage(&msg);
    }

   return (int) msg.wParam;
}

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg,
    WPARAM wParam, LPARAM lParam) {
  
    FLASHWINFO fwi;

    switch(msg)  {
    
      case WM_CREATE:

          CreateWindowW(L"Button", L"Flash",
                  WS_CHILD | WS_VISIBLE,
                  10, 10, 80, 25, 
                  hwnd, (HMENU) 1, NULL, NULL);
          break;

      case WM_COMMAND:

          fwi.cbSize = sizeof(fwi);
          fwi.dwFlags = FLASHW_ALL;
          fwi.dwTimeout = 0;
          fwi.hwnd = hwnd;
          fwi.uCount = 4;

          FlashWindowEx(&fwi);
          break;

      case WM_DESTROY:

          PostQuitMessage(0);
          break; 
    }

    return DefWindowProcW(hwnd, msg, wParam, lParam);
}