반투명 윈도우 만들기....플랫폼 SDK

#define _WIN32_WINNT 0x0501
#define WINVER  0x0501

#pragma comment(linker, "/subsystem:windows")

#include <windows.h>

LRESULT CALLBACK WndProc( HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
switch( msg )
{
case WM_CREATE:
  // 윈도우의 특정색을 투명하게 처리하고, 윈도우 전체에 반투명 효과를 준다.

  SetLayeredWindowAttributes(hwnd, 0, //투명처리할 색,
         200, //불투명 정도(0, 255)
         LWA_ALPHA);
  return 0;

case WM_LBUTTONDOWN:
  return 0;


case WM_DESTROY:
  PostQuitMessage(0);
  return 0;
}
return DefWindowProc( hwnd, msg, wParam, lParam);
}

int WINAPI WinMain( HINSTANCE hInstance, HINSTANCE hPrevInstance,
     LPSTR   lpCmdLine, int nShowCmd )
{
ATOM atom;
WNDCLASS wc;
HWND hwnd;
MSG msg;

wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
wc.hbrBackground= (HBRUSH)GetStockObject( WHITE_BRUSH );
wc.hCursor  = LoadCursor( 0, IDC_ARROW );
wc.hIcon  = LoadIcon( 0, IDI_APPLICATION);
wc.hInstance = hInstance;
wc.lpfnWndProc  = WndProc;
wc.lpszClassName= "First";
wc.lpszMenuName = 0;
wc.style  = 0;

atom = RegisterClass( &wc);

if ( atom == 0 )
{
  MessageBox( 0, "Fail To RegisterClass", "Error", MB_OK);
  return 0;
}

hwnd = CreateWindowEx( WS_EX_LAYERED, "first", "Hello", WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, 0, CW_USEDEFAULT,0, 0, 0,
        hInstance, 0);
ShowWindow( hwnd, nShowCmd);
UpdateWindow( hwnd );

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

return 0;
}