treelistviewitem.cs

树形列表控件

using System;
using System.Drawing;
using System.Runtime.InteropServices;
using System.ComponentModel;
using System.Runtime.InteropServices.APIs;
using System.Diagnostics;

namespace System.Windows.Forms
{
	#region TreeListViewItemBoundsPortion
	/// <summary>
	/// Specifies a portion of the tree list view item from which to retrieve the bounding rectangle
	/// </summary>
	[Serializable]
	public enum TreeListViewItemBoundsPortion
	{
		/// <summary>
		/// The bounding rectangle of the entire item, including the icon, the item text, and the subitem text (if displayed), should be retrieved
		/// </summary>
		Entire = (int)ItemBoundsPortion.Entire,
		/// <summary>
		/// The bounding rectangle of the icon or small icon should be retrieved
		/// </summary>
		Icon = (int)ItemBoundsPortion.Icon,
		/// <summary>
		/// The bounding rectangle specified by the Entire value without the subitems
		/// </summary>
		ItemOnly = (int)ItemBoundsPortion.ItemOnly,
		/// <summary>
		/// The bounding rectangle of the item text should be retrieved
		/// </summary>
		Label = (int)ItemBoundsPortion.Label,
		/// <summary>
		/// The bounding rectangle of the item plus minus
		/// </summary>
		PlusMinus = 4
	}
	#endregion
	/// <summary>
	/// Represents an item in a TreeListView control
	/// </summary>
	public class TreeListViewItem : ListViewItem
	{
		#region Private delegates
		private delegate void ChangeChildrenCheckStateRecursivelyHandler(CheckState state);
		private delegate TreeListViewItemCollection GetCollectionHandler();
		private delegate string GetStringHandler();
		private delegate bool GetBoolHandler();
		private delegate int GetIntHandler();
		private delegate TreeListViewItem GetTreeListViewItemHandler();
		#endregion

		#region Events
		/// <summary>
		/// TreeListViewItemHandler delegate
		/// </summary>
		public delegate void TreeListViewItemHanlder(object sender);
		/// <summary>
		/// TreeListViewItemCheckedHandler delegate
		/// </summary>
		public delegate void TreeListViewItemCheckedHandler(object sender, bool ischecked);
		/// <summary>
		/// Occurs after the tree node is collapsed
		/// </summary>
		public event TreeListViewItemHanlder AfterCollapse;
		/// <summary>
		/// Occurs after the tree node is expanded
		/// </summary>
		public event TreeListViewItemHanlder AfterExpand;
		#endregion
		#region Properties
			#region NextVisibleItem
			/// <summary>
			/// Gets the next visible item in the TreeListView
			/// </summary>
			public TreeListViewItem NextVisibleItem
			{
				get
				{
					if(!IsInATreeListView || !Visible) return null;
					ListView listview = (ListView) TreeListView;
					if(Index >= listview.Items.Count-1) return null;
					return (TreeListViewItem)listview.Items[Index+1];
				}
			}
			#endregion
			#region PrevVisibleItem
			/// <summary>
			/// Gets the previous visible item in the TreeListView
			/// </summary>
			public TreeListViewItem PrevVisibleItem
			{
				get
				{
					if(!IsInATreeListView || !Visible) return null;
					ListView listview = (ListView) TreeListView;
					if(Index < 1) return null;
					return (TreeListViewItem)listview.Items[Index-1];
				}
			}
			#endregion

			#region Checked properties
			/// <summary>
			/// Gets or sets a value indicating whether the item is checked.
			/// </summary>
			public new bool Checked 
			{
				get
				{
					try
					{
						return (base.Checked);
					}
					catch
					{
						return false;
					}
				}
				set 
				{
					if(IsInATreeListView)
						if(TreeListView.InvokeRequired)
							throw(new Exception("Invoke required"));
					try
					{
						// Check downwards recursively
						if(ListView != null &&
							ListView._checkDirection == CheckDirection.Downwards &&
							_items.Count > 0)
						{
							foreach(TreeListViewItem childItem in _items)
								childItem.Checked = value;
						}
						if(base.Checked == value) return;
						base.Checked = value;
					}
					catch{} 
				}
			}
			#endregion
			#region CheckStatus
			/// <summary>
			/// Gets the check state of this item
			/// </summary>
			public CheckState CheckStatus
			{
				get
				{
					if(_items.Count <= 0)
					{
						if(this.Checked)
							return CheckState.Checked;
						else
							return CheckState.Unchecked;
					}
					else
					{
						bool allChecked = true; 
						bool allUnChecked = true; 

						TreeListViewItem[] items = Items.ToArray(); 
						foreach(TreeListViewItem item in items) 
						{ 
							if (item.CheckStatus == CheckState.Indeterminate) 
								return CheckState.Indeterminate; 
							else if (item.CheckStatus == CheckState.Checked) 
								allUnChecked = false; 
							else 
								allChecked = false; 
						} 

						Debug.Assert(!(allChecked && allUnChecked)); 
						if (allChecked) 
							return CheckState.Checked; 
						else if (allUnChecked) 
							return CheckState.Unchecked; 
						else 
							return CheckState.Indeterminate; 
					}
				}
			}
			#endregion

			#region ParentsInHierarch
			/// <summary>
			/// Gets a collection of the parent of this item
			/// </summary>
			[Browsable(false)]
			public TreeListViewItem[] ParentsInHierarch
			{
				get
				{
					TreeListViewItemCollection items = GetParentsInHierarch();
					return(items.ToArray());
				}
			}
			private TreeListViewItemCollection GetParentsInHierarch()
			{
				TreeListViewItemCollection temp = Parent != null ?
					Parent.GetParentsInHierarch() : new TreeListViewItemCollection();
				if(Parent != null) temp.Add(Parent);
				return temp;
			}
			#endregion
			#region FullPath
			/// <summary>
			/// Gets the fullpath of an item (Parents.Text + \ + this.Text)
			/// </summary>
			[Browsable(false)]
			public string FullPath
			{
				get
				{
					if(Parent != null)
					{
						string pathSeparator = IsInATreeListView ? TreeListView.PathSeparator : "\\";
						string strPath = Parent.FullPath + pathSeparator + Text;
						return(strPath.Replace(pathSeparator + pathSeparator, pathSeparator));
					}
					else
						return(Text);
				}
			}
			#endregion
			#region Text
			/// <summary>
			/// Get or Set the Text property
			/// </summary>
			new public string Text
			{
				get
				{
					return(base.Text);
				}
				set
				{
					base.Text = value;
					TreeListViewItemCollection collection = Container;
					if(collection != null) collection.Sort(false);}
			}
			#endregion
			#region Container
			/// <summary>
			/// Get the collection that contains this item
			/// </summary>
			public TreeListViewItemCollection Container
			{
				get
				{
					if(Parent != null) return(Parent.Items);
					if(IsInATreeListView) return(TreeListView.Items);
					return(null);
				}
			}
			#endregion
			#region IsInATreeListView
			internal bool IsInATreeListView
			{
				get
				{
					return(TreeListView != null);
				}
			}
			#endregion
			#region LastChildIndexInListView
			/// <summary>
			/// Get the biggest index in the listview of the visible childs of this item
			/// including this item
			/// </summary>
			[Browsable(false)]
			public int LastChildIndexInListView
			{
				get
				{
					if(!IsInATreeListView)
						throw(new Exception("No ListView control"));
					int index = this.Index, temp;
					foreach(TreeListViewItem item in Items)
						if(item.Visible)
						{
							temp = item.LastChildIndexInListView;
							if(temp > index) index = temp;
						}
					return(index);
				}
			}
			#endregion
			#region ChildrenCount
			/// <summary>
			/// Get the children count recursively
			/// </summary>
			[Browsable(false)]
			public int ChildrenCount
			{
				get
				{
					TreeListViewItem[] items = _items.ToArray();
					int count = items.Length;
					foreach(TreeListViewItem item in items) count += item.ChildrenCount;
					return(count);
				}
			}
			#endregion
			#region IsExpanded
			private bool _isexpanded;
			/// <summary>
			/// Returns true if this item is expanded
			/// </summary>
			public bool IsExpanded
			{
				get
				{
					return(_isexpanded);
				}
				set
				{
					if(_isexpanded == value) return;
					if(value) Expand();
					else Collapse();
				}
			}
			#endregion
			#region Level
			/// <summary>
			/// Get the level of the item in the treelistview
			/// </summary>
			[Browsable(false)]
			public int Level
			{
				get
				{
					return(Parent == null ? 0 : Parent.Level + 1);
				}
			}
			#endregion
			#region Items
			private TreeListViewItemCollection _items;
			/// <summary>
			/// Get the items contained in this item
			/// </summary>
			public TreeListViewItemCollection Items
			{
				get
				{
					return(_items);
				}
			}
			#endregion
			#region Parent
			private TreeListViewItem _parent;
			/// <summary>
			/// Get the parent of this item
			/// </summary>
			public TreeListViewItem Parent
			{
				get
				{
					return(_parent);
				}
			}
			#endregion
			#region TreeListView
			/// <summary>
			/// Gets the TreeListView containing this item
			/// </summary>
			public new TreeListView ListView
			{
				get
				{
					if(base.ListView != null) return((TreeListView) base.ListView);
					if(Parent != null) return(Parent.ListView);
					return(null);
				}
			}
			/// <summary>
			/// Gets the TreeListView containing this item
			/// </summary>
			public TreeListView TreeListView
			{
				get
				{
					return (TreeListView) ListView;
				}
			}
			#endregion
			#region Visible
			/// <summary>
			/// Returns true if this item is visible in the TreeListView
			/// </summary>
			public bool Visible
			{
				get
				{
					return(base.Index > -1);
				}
			}
			#endregion
		#endregion

		#region Constructors
		/// <summary>
		/// Create a new instance of a TreeListViewItem
		/// </summary>
		public TreeListViewItem()
		{
			_items = new TreeListViewItemCollection(this);
		}
		/// <summary>
		/// Create a new instance of a TreeListViewItem
		/// </summary>
		public TreeListViewItem(string value) : this()
		{
			this.Text = value;
		}
		/// <summary>
		/// Create a new instance of a TreeListViewItem
		/// </summary>
		public TreeListViewItem(string value, int imageindex) : this(value)
		{
			this.ImageIndex = imageindex;
		}
		#endregion
		
		#region Functions
		internal void GetCheckedItems(ref TreeListViewItemCollection items)
		{
			if(Checked) items.Add(this);
			foreach(TreeListViewItem item in Items)
				item.GetCheckedItems(ref items);
		}
		/// <summary>
		/// Places the subitem into edit mode
		/// </summary>
		/// <param name="column">Number of the subitem to edit</param>
		public void BeginEdit(int column)
		{
			if(TreeListView == null)
				throw(new Exception("The item is not associated with a TreeListView"));
			if(!TreeListView.Visible)
				throw(new Exception("The item is not visible"));
			if(column + 1 > TreeListView.Columns.Count)
				throw(new Exception("The column is greater the number of columns in the TreeListView"));
			TreeListView.Focus();
			Focused = true;
			TreeListView._lastitemclicked = new EditItemInformations(this, column, this.SubItems[column].Text);
			base.BeginEdit();
		}
		/// <summary>
		/// Places the item into edit mode
		/// </summary>
		new public void BeginEdit()
		{
			BeginEdit(0);
		}
		/// <summary>
		/// Asks the associated TreeListView control to redraw this item
		/// </summary>
		public void Redraw()
		{
			if(ListView == null || !Visible) return;
			try
			{
				APIsUser32.SendMessage(
					ListView.Handle,
					(int)APIsEnums.ListViewMessages.REDRAWITEMS,
					Index, Index);}
			catch{}
		}
		/// <summary>
		/// Retrieves the specified portion of the bounding rectangle for the item
		/// </summary>
		/// <param name="portion">One of the TreeListViewItemBoundsPortion values that represents a portion of the item for which to retrieve the bounding rectangle</param>
		/// <returns>A Rectangle that represents the bounding rectangle for the specified portion of the item</returns>
		public Rectangle GetBounds(TreeListViewItemBoundsPortion portion)
		{
			switch((int)portion)
			{
				case (int) TreeListViewItemBoundsPortion.PlusMinus:
					if(TreeListView == null)
						throw(new Exception("This item is not associated with a TreeListView control"));
					Point pos = base.GetBounds(ItemBoundsPortion.Entire).Location;
					Point position = new Point(
						Level*SystemInformation.SmallIconSize.Width + 1 + pos.X,
						TreeListView.GetItemRect(Index, ItemBoundsPortion.Entire).Top + 1);
					return new Rectangle(position, TreeListView.ShowPlusMinus ? SystemInformation.SmallIconSize : new Size(0, 0));
				default:
					ItemBoundsPortion lviPortion = (ItemBoundsPortion)(int) portion;
					return base.GetBounds(lviPortion);
			}
		}
		internal void SetParent(TreeListViewItem parent)
		{
			_parent = parent;
		}
		/// <summary>
		/// Remove this item from its associated collection
		/// </summary>
		public new void Remove()
		{