Node.cs :  » GUI » TreeViewAdv » Aga » Controls » Tree » C# / CSharp Open Source

using System;
using System.Collections.Generic;
using System.Text;
using System.Collections.ObjectModel;
using System.Windows.Forms;
using System.Drawing;

namespace Aga.Controls.Tree{
  public class Node
  {
    #region NodeCollection

    private class NodeCollection : Collection<Node>
    {
      private Node _owner;

      public NodeCollection(Node owner)
      {
        _owner = owner;
      }

      protected override void ClearItems()
      {
        while (this.Count != 0)
          this.RemoveAt(this.Count - 1);
      }

      protected override void InsertItem(int index, Node item)
      {
        if (item == null)
          throw new ArgumentNullException("item");

        if (item.Parent != _owner)
        {
          if (item.Parent != null)
            item.Parent.Nodes.Remove(item);
          item._parent = _owner;
          item._index = index;
          for (int i = index; i < Count; i++)
            this[i]._index++;
          base.InsertItem(index, item);

          TreeModel model = _owner.FindModel();
          if (model != null)
            model.OnNodeInserted(_owner, index, item);
        }
      }

      protected override void RemoveItem(int index)
      {
        Node item = this[index];
        item._parent = null;
        item._index = -1;
        for (int i = index + 1; i < Count; i++)
          this[i]._index--;
        base.RemoveItem(index);

        TreeModel model = _owner.FindModel();
        if (model != null)
          model.OnNodeRemoved(_owner, index, item);
      }

      protected override void SetItem(int index, Node item)
      {
        if (item == null)
          throw new ArgumentNullException("item");

        RemoveAt(index);
        InsertItem(index, item);
      }
    }

    #endregion

    #region Properties

    private TreeModel _model;
    internal TreeModel Model
    {
      get { return _model; }
      set { _model = value; }
    }

    private NodeCollection _nodes;
    public Collection<Node> Nodes
    {
      get { return _nodes; }
    }

    private Node _parent;
    public Node Parent
    {
      get { return _parent; }
      set 
      {
        if (value != _parent)
        {
          if (_parent != null)
            _parent.Nodes.Remove(this);

          if (value != null)
            value.Nodes.Add(this);
        }
      }
    }

    private int _index = -1;
    public int Index
    {
      get
      {
        return _index;
      }
    }

    public Node PreviousNode
    {
      get
      {
        int index = Index;
        if (index > 0)
          return _parent.Nodes[index - 1];
        else
          return null;
      }
    }

    public Node NextNode
    {
      get
      {
        int index = Index;
        if (index >= 0 && index < _parent.Nodes.Count - 1)
          return _parent.Nodes[index + 1];
        else
          return null;
      }
    }

    private string _text;
    public virtual string Text
    {
      get { return _text; }
      set 
      {
        if (_text != value)
        {
          _text = value;
          NotifyModel();
        }
      }
    }

    private CheckState _checkState;
    public virtual CheckState CheckState
    {
      get { return _checkState; }
      set 
      {
        if (_checkState != value)
        {
          _checkState = value;
          NotifyModel();
        }
      }
    }

    private Image _image;
    public Image Image
    {
      get { return _image; }
      set 
      {
        if (_image != value)
        {
          _image = value;
          NotifyModel();
        }
      }
    }

    private object _tag;
    public object Tag
    {
      get { return _tag; }
      set { _tag = value; }
    }

    public bool IsChecked
    {
      get 
      { 
        return CheckState != CheckState.Unchecked;
      }
      set 
      {
        if (value)
          CheckState = CheckState.Checked;
        else
          CheckState = CheckState.Unchecked;
      }
    }

    public virtual bool IsLeaf
    {
      get
      {
        return false;
      }
    }

    #endregion

    public Node()
      : this(string.Empty)
    {
    }

    public Node(string text)
    {
      _text = text;
      _nodes = new NodeCollection(this);
    }

    public override string ToString()
    {
      return Text;
    }

    private TreeModel FindModel()
    {
      Node node = this;
      while (node != null)
      {
        if (node.Model != null)
          return node.Model;
        node = node.Parent;
      }
      return null;
    }

    protected void NotifyModel()
    {
      TreeModel model = FindModel();
      if (model != null && Parent != null)
      {
        TreePath path = model.GetPath(Parent);
        if (path != null)
        {
          TreeModelEventArgs args = new TreeModelEventArgs(path, new int[] { Index }, new object[] { this });
          model.OnNodesChanged(args);
        }
      }
    }
  }
}