ExcelDna.IntelliSense.ExcelToolTipWatcher.GetLastToolTipOrZero C# (CSharp) Метод

        public IntPtr GetLastToolTipOrZero() => _toolTips.Count > 0 ? _toolTips[_toolTips.Count - 1] : IntPtr.Zero;
        // CONSIDER: Rather a Stack? Check the assumption that Hide happens in reverse order

        void _excelToolTipWatcher_ToolTipChanged(object sender, ExcelToolTipWatcher.ToolTipChangeEventArgs e)
        {
            // We assume the ExcelToolTip changes happen before the corresponding FunctionList / FormulaEdit changes
            // So we keep track of the last shown one.
            // This allows the FormulaEdit or transitions to pick it up, hopefully not getting confused with the FunctionList tooltip
            // TODO: Check that the tooltip gets cleared from the CurrentState is it is hidden

            Logger.Monitor.Verbose($"!> ExcelToolTip ToolTipChanged Received: {e} with state: {CurrentState.GetType().Name}");

            if (e.ChangeType == ExcelToolTipWatcher.ToolTipChangeType.Show)
            {
                _lastExcelToolTipShown = e.Handle;
            }
            else if (e.ChangeType == ExcelToolTipWatcher.ToolTipChangeType.Hide)
            {
                if (_lastExcelToolTipShown == e.Handle)
                {
                    _lastExcelToolTipShown = _excelToolTipWatcher.GetLastToolTipOrZero();
                }

                var fe = CurrentState as UIState.FormulaEdit;
                if (fe != null)
                {
                    // Either a FormulaEdit or a FunctionList
                    if (fe.ExcelToolTipWindow == e.Handle)
                    {
                        // OK - it's no longer valid
                        // TODO: Manage the state update
                        // This is a kind of pop.... is it right?
                        var newState = fe.WithToolTipWindow(_lastExcelToolTipShown);
                        OnStateChanged(newState);
                    }
                }
            }
        }