System.Windows.Controls.AutoCompleteBox.ClosingDropDown C# (CSharp) Méthode

        private void ClosingDropDown(bool oldValue)
        {
            bool delayedClosingVisual = false;
            if(DropDownPopup != null)
            {
                delayedClosingVisual = DropDownPopup.UsesClosingVisualState;
            }

#if SILVERLIGHT
            RoutedPropertyChangingEventArgs<bool> args = new RoutedPropertyChangingEventArgs<bool>(IsDropDownOpenProperty, oldValue, false, true);
#else
            RoutedPropertyChangingEventArgs<bool> args = new RoutedPropertyChangingEventArgs<bool>(IsDropDownOpenProperty, oldValue, false, true, DropDownClosingEvent);
#endif

            OnDropDownClosing(args);

            if(_view == null || _view.Count == 0)
            {
                delayedClosingVisual = false;
            }

            if(args.Cancel)
            {
                _ignorePropertyChange = true;
                SetValue(IsDropDownOpenProperty, oldValue);
            }
            else
            {
                // Immediately close the drop down window:
                // When a popup closed visual state is present, the code path is 
                // slightly different and the actual call to CloseDropDown will 
                // be called only after the visual state's transition is done
                RaiseExpandCollapseAutomationEvent(oldValue, false);
                if(!delayedClosingVisual)
                {
                    CloseDropDown(oldValue, false);
                }
            }

            UpdateVisualState(true);
        }