Synchronize the Net40

Net40/HandyControl_Net40/Controls/Base/SelectableItem.cs

@@ -29,11 +29,38 @@ namespace HandyControl.Controls
 
             if (_isMouseLeftButtonDown)
             {
-                RaiseEvent(new RoutedEventArgs(SelectedEvent, this));
+                if (SelfManage)
+                {
+                    if (!IsSelected)
+                    {
+                        IsSelected = true;
+                        OnSelected(new RoutedEventArgs(SelectedEvent, this));
+                    }
+                    else if (CanDeselect)
+                    {
+                        IsSelected = false;
+                        OnSelected(new RoutedEventArgs(DeselectedEvent, this));
+                    }
+                }
+                else
+                {
+                    if (CanDeselect)
+                    {
+                        OnSelected(IsSelected
+                            ? new RoutedEventArgs(DeselectedEvent, this)
+                            : new RoutedEventArgs(SelectedEvent, this));
+                    }
+                    else
+                    {
+                        OnSelected(new RoutedEventArgs(SelectedEvent, this));
+                    }
+                }
                 _isMouseLeftButtonDown = false;
             }
         }
 
+        protected virtual void OnSelected(RoutedEventArgs e) => RaiseEvent(e);
+
         public static readonly DependencyProperty IsSelectedProperty = DependencyProperty.Register(
             "IsSelected", typeof(bool), typeof(SelectableItem), new PropertyMetadata(ValueBoxes.FalseBox));
 
@@ -43,6 +70,24 @@ namespace HandyControl.Controls
             set => SetValue(IsSelectedProperty, value);
         }
 
+        public static readonly DependencyProperty SelfManageProperty = DependencyProperty.Register(
+            "SelfManage", typeof(bool), typeof(SelectableItem), new PropertyMetadata(ValueBoxes.FalseBox));
+
+        public bool SelfManage
+        {
+            get => (bool)GetValue(SelfManageProperty);
+            set => SetValue(SelfManageProperty, value);
+        }
+
+        public static readonly DependencyProperty CanDeselectProperty = DependencyProperty.Register(
+            "CanDeselect", typeof(bool), typeof(SelectableItem), new PropertyMetadata(ValueBoxes.FalseBox));
+
+        public bool CanDeselect
+        {
+            get => (bool)GetValue(CanDeselectProperty);
+            set => SetValue(CanDeselectProperty, value);
+        }
+
         public static readonly RoutedEvent SelectedEvent =
             EventManager.RegisterRoutedEvent("Selected", RoutingStrategy.Bubble,
                 typeof(RoutedEventHandler), typeof(SelectableItem));
@@ -52,5 +97,15 @@ namespace HandyControl.Controls
             add => AddHandler(SelectedEvent, value);
             remove => RemoveHandler(SelectedEvent, value);
         }
+
+        public static readonly RoutedEvent DeselectedEvent =
+            EventManager.RegisterRoutedEvent("Deselected", RoutingStrategy.Bubble,
+                typeof(RoutedEventHandler), typeof(SelectableItem));
+
+        public event RoutedEventHandler Deselected
+        {
+            add => AddHandler(DeselectedEvent, value);
+            remove => RemoveHandler(DeselectedEvent, value);
+        }
     }
 }