WPFのXAMLで複数選択ComboBox

XAMLで複数選択できるComboBoxするメモ
参考サイトのIListがよく知らなかったので、Dictionaryに戻して利用した更新差分

        public static readonly DependencyProperty ItemsSourceProperty =
             DependencyProperty.Register("ItemsSource", typeof(Dictionary<string, object>), typeof(MultiSelectComboBox), new PropertyMetadata(null,
        new PropertyChangedCallback(MultiSelectComboBox.OnItemsSourceChanged)));

        public static readonly DependencyProperty SelectedItemsProperty =
         DependencyProperty.Register("SelectedItems", typeof(Dictionary<string, object>), typeof(MultiSelectComboBox), new PropertyMetadata(null,
     new PropertyChangedCallback(MultiSelectComboBox.OnSelectedItemsChanged)));

        public static readonly DependencyProperty TextProperty =
           DependencyProperty.Register("Text", typeof(string), typeof(MultiSelectComboBox), new PropertyMetadata(null));

        public static readonly DependencyProperty DefaultTextProperty =
            DependencyProperty.Register("DefaultText", typeof(string), typeof(MultiSelectComboBox), new PropertyMetadata(null));



        public Dictionary<string, object> ItemsSource
        {
            get { return (Dictionary<string, object>)GetValue(ItemsSourceProperty); }
            set
            {
                SetValue(ItemsSourceProperty, value);
            }
        }

        public Dictionary<string, object> SelectedItems
        {
            get { return (Dictionary<string, object>)GetValue(SelectedItemsProperty); }
            set
            {
                SetValue(SelectedItemsProperty, value);
            }
        }

        private void SetSelectedItems()
        {
            if (SelectedItems == null)
                SelectedItems = new Dictionary<string, object>();
            SelectedItems.Clear();
            foreach (Node node in _nodeList)
            {
                if (node.IsSelected && node.Title != "All")
                {
                    if (this.ItemsSource.Count > 0)

                        SelectedItems.Add(node.Title, this.ItemsSource[node.Title]);
                }
            }
        }

参考サイト