Sets the visual style of the tool tip window.
HRESULT SetWindowTheme( 
   LPCWSTR pszSubAppName  
);
Parameters
- pszSubAppName
 A pointer to a Unicode string that contains the visual style to set.
Return Value
The return value is not used.
Remarks
This member function emulates the functionality of the TTM_SETWINDOWTHEME message, as described in the Windows SDK.
Requirements
Header: afxcmn.h