Summary:

http://msdn.microsoft.com/en-us/library/ms628748(VS.85).aspx

The ITfLangBarMgr interface is implemented by the TSF manager and used by text services to manage event sink notification and configure floating language bar display settings. The interface ID is IID_ITfLangBarMgr.

C# Definition:

[ComImport]
[ComVisible(false)]
[InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
[Guid("87955690-e627-11d2-8ddb-00105a2799b5")]
  interface ITfLangBarMgr {
      ///virtual HRESULT STDMETHODCALLTYPE AdviseEventSink(
      ///    /* [in] */ ITfLangBarEventSink *pSink,
      ///    /* [in] */ HWND hwnd,
      ///    /* [in] */ DWORD dwFlags,
      ///    /* [in] */ DWORD *pdwCookie) = 0;
      int AdviseEventSink(IUnknown pSink, IntPtr hwnd, uint dwFlags, ref uint pdwCookie);

      ///virtual HRESULT STDMETHODCALLTYPE UnadviseEventSink(
      ///    /* [in] */ DWORD dwCookie) = 0;
      int UnadviseEventSing(uint dwCookie);

      ///virtual HRESULT STDMETHODCALLTYPE GetThreadMarshalInterface(
      ///    /* [in] */ DWORD dwThreadId,
      ///    /* [in] */ DWORD dwType,
      ///    /* [in] */ REFIID riid,
      ///    /* [iid_is][out] */ IUnknown **ppunk) = 0;
      int GetThreadMarshalInterface(uint dwThreadId, uint dwType,
      [In, MarshalAs(UnmanagedType.LPStruct)] Guid riid, ref IntPtr ppunk);

      ///virtual HRESULT STDMETHODCALLTYPE GetThreadLangBarItemMgr(
      ///    /* [in] */ DWORD dwThreadId,
      ///    /* [out] */ ITfLangBarItemMgr **pplbi,
      ///    /* [out] */ DWORD *pdwThreadid) = 0;
      int GetThreadLangBarItemMgr(uint dwTrheadId, ITfLangBarMgr pplbi, uint pdwThreadid);

      ///virtual HRESULT STDMETHODCALLTYPE GetInputProcessorProfiles(
      ///    /* [in] */ DWORD dwThreadId,
      ///    /* [out] */ ITfInputProcessorProfiles **ppaip,
      ///    /* [out] */ DWORD *pdwThreadid) = 0;
      int GetInputProcessorProfiles(uint dwThreadId, ref IUnknown ppaip, ref uint pdwThreadId);

      ///virtual HRESULT STDMETHODCALLTYPE RestoreLastFocus(
      ///    /* [out] */ DWORD *pdwThreadId,
      ///    /* [in] */ BOOL fPrev) = 0;
      int RestoreLastFocus(ref uint pdwThreadId,
      [MarshalAs(UnmanagedType.Bool)] bool fPrev);

      ///virtual HRESULT STDMETHODCALLTYPE SetModalInput(
      ///    /* [in] */ ITfLangBarEventSink *pSink,
      ///    /* [in] */ DWORD dwThreadId,
      ///    /* [in] */ DWORD dwFlags) = 0;
      int SetModalInput(IUnknown pSink, uint dwThreadId, uint dwFlags);

      ///virtual HRESULT STDMETHODCALLTYPE ShowFloating(
      ///    /* [in] */ DWORD dwFlags) = 0;
      int ShowFloating(uint dwFlags);

      ///virtual HRESULT STDMETHODCALLTYPE GetShowFloatingStatus(
      ///    /* [out] */ DWORD *pdwFlags) = 0;
      int GetShowFloatingStatus(ref uint pdwFlags);
}

VB Definition:

<ComImport> _
<Guid("TODO")> _
'TODO: Insert <InterfaceType(ComInterfaceType.InterfaceIsIUnknown)> _ if this doesn't derive from IDispatch
Interface ITfLangBarMgr
   TODO
End Interface

User-Defined Types:

Notes:

Here's how I instantiated this:

    Type classtype = Type.GetTypeFromCLSID(CLSID_TF_LangBarMgr, true);
    object langbarObject = System.Activator.CreateInstance(classtype);
    ITfLangBarMgr langBarMgr = langbarObject as ITfLangBarMgr;