private static void AddCommandFilter(IVsTextView viewAdapter, HighlightUsageFilter commandFilter)
        {
            if (!commandFilter.IsAdded)
            {
                // Get the view adapter from the editor factory
                IOleCommandTarget next;
                int hr = viewAdapter.AddCommandFilter(commandFilter, out next);

                if (hr == VSConstants.S_OK)
                {
                    commandFilter.IsAdded = true;
                    // You'll need the next target for Exec and QueryStatus
                    if (next != null) commandFilter.NextTarget = next;
                }
            }
        }
        private static void AddCommandFilter(IVsTextView viewAdapter, HighlightUsageFilter commandFilter)
        {
            if (!commandFilter.IsAdded)
            {
                // Get the view adapter from the editor factory
                IOleCommandTarget next;
                int hr = viewAdapter.AddCommandFilter(commandFilter, out next);

                if (hr == VSConstants.S_OK)
                {
                    commandFilter.IsAdded = true;
                    // You'll need the next target for Exec and QueryStatus
                    if (next != null)
                    {
                        commandFilter.NextTarget = next;
                    }
                }
            }
        }