DirectDraw Applications and Window Styles (Windows Embedded CE 6.0)
1/6/2010
If your application uses DirectDraw in windowed mode, you can create windows with any window style. However, full-screen exclusive mode applications cannot be created with the WS_EX_TOOLWINDOW style without risk of unpredictable behavior.
The WS_EX_TOOLWINDOW style prevents a window from being the top most window, which is required for a DirectDraw full-screen, exclusive mode application.
Full-screen exclusive mode applications should use the WS_EX_TOPMOST extended window style and the WS_VISIBLE window style to display properly. These styles keep the application at the front of the window z-order and prevent GDI from drawing on the primary surface.
The following example shows one way to prepare a window to be used in a full-screen, exclusive mode application.
////////////////////////////////////////////////////////
// Register the window class, display the window, and init
// all DirectX and graphic objects.
////////////////////////////////////////////////////////
BOOL WINAPI InitApp(INT nWinMode)
{
WNDCLASSEX wcex;
wcex.cbSize = sizeof(WNDCLASSEX);
wcex.hInstance = g_hinst;
wcex.lpszClassName = g_szWinName;
wcex.lpfnWndProc = WndProc;
wcex.style = CS_VREDRAW|CS_HREDRAW|CS_DBLCLKS;
wcex.hIcon = LoadIcon (NULL, IDI_APPLICATION);
wcex.hIconSm = LoadIcon (NULL, IDI_WINLOGO);
wcex.hCursor = LoadCursor (NULL, IDC_ARROW);
wcex.lpszMenuName = MAKEINTRESOURCE(IDR_APPMENU);
wcex.cbClsExtra = 0 ;
wcex.cbWndExtra = 0 ;
wcex.hbrBackground = GetStockObject (NULL_BRUSH);
RegisterClassEx(&wcex);
g_hwndMain = CreateWindowEx(
WS_EX_TOPMOST,
g_szWinName,
g_szWinCaption,
WS_VISIBLE|WS_POPUP,
0,0,CX_SCREEN,CY_SCREEN,
NULL,
NULL,
g_hinst,
NULL);
if(!g_hwndMain)
return(FALSE);
SetFocus(g_hwndMain);
ShowWindow(g_hwndMain, nWinMode);
UpdateWindow(g_hwndMain);
return TRUE;
}