// TreeViewItem class
		public event PropertyChangedEventHandler PropertyChanged = (x, y) => { };

		[SerializeField]
		[UnityEngine.Serialization.FormerlySerializedAs("ComboboxItems")] // without it data will be lost on renaming
		List<string> comboboxItems;

		public List<string> ComboboxItems
		{
			get
			{
				return comboboxItems
			}

			set
			{
				comboboxItems = value;
				Changed("ComboboxItems");
			}
		}

		protected void Changed(string propertyName)
		{
			PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
		}

		TreeViewItem item;

// TreeViewItemComponent
		public TreeViewItem Item
		{
			get
			{
				return item;
			}

			set
			{
				if (item != null)
				{
					item.PropertyChanged -= UpdateView;
				}

				item = value;

				if (item != null)
				{
					item.PropertyChanged += UpdateView;
				}

				UpdateView();
			}
		}

		public override void SetData(TreeNode<TreeViewItem> node, int depth)
		{
			Node = node;
			base.SetData(Node, depth);

			Item = (Node == null) ? null : Node.Item;
		}

		protected void UpdateView(object sender = null, PropertyChangedEventArgs ev = null)
		{
			// set combobox items, selected index and other data
		}