WM_SIZE incorrect values?

This is my window class definition:

wcex.cbSize = sizeof(WNDCLASSEX);

wcex.style            = CS_HREDRAW | CS_VREDRAW;
wcex.lpfnWndProc            = (WNDPROC)WndProc;
wcex.cbClsExtra            = 0;
wcex.cbWndExtra            = 0;
wcex.hInstance            = hInstance;
wcex.hIcon            = LoadIcon(hInstance, (LPCTSTR)IDI_GROUPBOX);
wcex.hCursor            = LoadCursor(NULL, IDC_ARROW);
wcex.hbrBackground      = (HBRUSH)GetStockObject(LTGRAY_BRUSH);//(HBRUSH)(COLOR_WINDOW+1);
wcex.lpszMenuName      = (LPCSTR)IDC_GROUPBOX;
wcex.lpszClassName      = szWindowClass;
wcex.hIconSm            = LoadIcon(wcex.hInstance, (LPCTSTR)IDI_SMALL);

In the wndproc for the window I take the width and height from lParam:

case WM_SIZE:
{
      gnWidth  = LOWORD( lParam );
      gnHeight = HIWORD( lParam );
      InvalidateRect( hWnd, NULL, TRUE );
      break;
}

I also did

RECT r;
GetClientRect( hWnd, &r );

but the size was exactly as that sent from Windows to my wndproc via lParam.

Oh, almost forgot:
case WM_PAINT:
{
      hdc = BeginPaint(hWnd, &ps);
      RECT rt;
      TCHAR szSize[100];
      _stprintf( szSize, _T("%dx%d"), gnWidth, gnHeight );
      GetClientRect(hWnd, &rt);
      DrawText(hdc, szSize, strlen(szSize), &rt, DT_CENTER);
      EndPaint(hWnd, &ps);
      break;
}

/rob

I could not see that any height was off by anything when I tried that.

So either use that code or post some for me to look at ;-)

/rob

I also tried my sizing stuff through the values in lParam with the WM_SIZE message, even tried dabbling with WM_SIZING. But I noticed those were also off in exactly the same way GetClientRect was. I will try you're code anyways, just for the hell of it... I will post my findings here shortly, along with some snippets for you to look at

Ok, I found the problem. When resizing a Listbox, somehow it's not right. The following code displays my problem (try it and then resize the window, you'll see the problem on the bottom of the window). This behaviour is not displayed if you replace the WC_LISTBOX with a WC_EDIT, for example.

*** CODE ****

HWND listbox;

void AllignInnerWindow(int width,int height){
      SetWindowPos(edit,NULL,0,0,width,height,SWP_NOZORDER);
}

LRESULT CALLBACK WndProc(HWND hWnd,UINT Msg,WPARAM wParam,LPARAM lParam){
      switch(Msg){
            case WM_SIZE:
                  RECT r;
                  GetClientRect(hWnd,&r);
                  AllignInnerWindow(r.right,r.bottom);
            break;
      }
      return DefWindowProc(hWnd,Msg,wParam,lParam);
}

int APIENTRY WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance,LPTSTR lpCmdLine,int nCmdShow){
      WNDCLASSEX wcex;

      wcex.cbSize = sizeof(WNDCLASSEX);

      wcex.style          = NULL;
      wcex.lpfnWndProc    = DefWindowProc;
      wcex.cbClsExtra     = 0;
      wcex.cbWndExtra     = 0;
      wcex.hInstance      = hInstance;
      wcex.hIcon          = NULL;
      wcex.hCursor        = LoadCursor(NULL, IDC_ARROW);
      wcex.hbrBackground  = (HBRUSH)GetStockObject(LTGRAY_BRUSH);
      wcex.lpszMenuName   = NULL;
      wcex.lpszClassName  = "myWindowClass";
      wcex.hIconSm        = NULL;
      
      RegisterClassEx(&wcex);

      HWND main = CreateWindow("myWindowClass","Main Window",WS_OVERLAPPEDWINDOW|WS_VISIBLE,200,200,400,400,NULL,NULL,hInstance,NULL);
      SetWindowLong(main,GWL_WNDPROC,(LONG)WndProc);
      listbox = CreateWindow(WC_LISTBOX,"",WS_CHILD|WS_VISIBLE,0,0,20,20,main,NULL,hInstance,NULL);
            
      MSG msg;
      while (GetMessage(&msg, NULL, 0, 0))
      {
            TranslateMessage(&msg);
            DispatchMessage(&msg);
      }

      return (int) msg.wParam;
}

*** END CODE ***

Whoops !!

In the above code, replace "edit" by "listbox" in the AllignInnerWindow function.