ActionScript实现TreeView数据结构

     由于ActionScript语言的动态特性，flex中所有树形结构数据都是直接使用xml进行处理的，虽然非常灵活，但是在使用时也会感到不方便，因此不妨实现一个Treeview的数据结构，并以此数据结构作为mxml中的数据源，使用起来就会方便很多了。

TreeNode的代码：

package com.sample.Control
{
	import mx.collections.ArrayCollection;
	
	[Bindable]
	public dynamic class TreeNode
	{
		public var text:String="";
		public var value:String="";
		public var url:String="";
		public var Target:String="";
		public var ShowCheckBox:Boolean=false;
		public var Checked:Boolean=false;
		public var Depth:int=0;
		public var Expanded:Boolean=false;
		public var ImageTooltip:String="";
		public var ImageUrl:String="";
		public var Selected:Boolean=false;
		public var Tooltip:String="";
		public var Children:ArrayCollection=null;
		
		public function TreeNode(xml:XML)
		{
			if(xml==null)
				return;
			this.text = xml.TEXT||xml.@TEXT||xml.@text||xml.text;
			this.value = xml.VALUE||xml.@VALUE||xml.@value||xml.value;
			this.url = xml.URL||xml.@URL||xml.@url||xml.url;
			this.Target = xml.TARGET||xml.@TARGET||xml.@Target||xml.Target;
			var showCheckBox:String = xml.SHOWCHECKBOX||xml.@SHOWCHECKBOX||
										xml.@ShowCheckBox||xml.ShowCheckBox;
			this.ShowCheckBox = showCheckBox=="true";
			var checked:String = xml.CHECKED||xml.@CHECKED||xml.@Checked||xml.Checked;
			this.Checked = checked=="true";
			var expand:String = xml.EXPANDED||xml.@EXPANDED||
							xml.@Expanded||xml.Expanded;
			this.Expanded = expand=="true";
			if(xml.DEPTH!=undefined){
				this.Depth = xml.DEPTH;
			}
			this.ImageTooltip = xml.IMAGETOOLTIP||xml.@IMAGETOOLTIP||
								xml.@ImageTooltip||xml.ImageTooltip;
								
			this.ImageUrl = xml.IMAGEURL||xml.@IMAGEURL||
								xml.@ImageUrl||xml.ImageUrl;
			if(xml.SELECTED!=undefined){
				this.Selected = xml.SELECTED=="true";
			}
			if(xml.TOOLTIP!=undefined){
				this.Tooltip = xml.TOOLTIP;
			}
			if(xml.CHILDNODES!=undefined && xml.CHILDNODES.length()>0){
				var cNodes:ArrayCollection = new ArrayCollection();
				for(var index:int=0;index
  
   length();index++){
						
   var xNode:XML = xml.CHILDNODES.child(index)[0];
						
   if(xNode!=
   null){
			 				cNodes.addItem(
   new TreeNode(xNode));
			 		}
			 	}
				
   this.Children = cNodes;
			}
		}
	
		
   ///转换为XML
		
   public 
   function ToXML():XML{
			
   var node:XML = 
   new XML("
   
    ");
			node.@text = 
   this.text;
			node.@value = 
   this.value;
			node.@Checked = 
   this.Checked;
			node.@Depth = 
   this.Depth;
			node.@Expanded = 
   this.Expanded;
			node.@ImageTooltip = 
   this.ImageTooltip;
			node.@ImageUrl = 
   this.ImageUrl;
			node.@Selected = 
   this.Selected;
			node.@ShowCheckBox = 
   this.ShowCheckBox;
			node.@Target = 
   this.Target;
			node.@Tooltip = 
   this.Tooltip;
			node.@url = 
   this.url;
			
   if(
   this.Children!=
   null && 
   this.Children.
   length>0){
				
   for each(
   var cNode:TreeNode 
   in 
   this.Children){
					node.appendChild(cNode.ToXML());
				}
			}
			
   return node;
		}
	}
}
  

TreeView的代码：

package com.sample.Control
{
	import mx.collections.ArrayCollection;
	
	///Tree控件的数据源容器
	public dynamic class TreeView
	{
		private var m_Nodes:ArrayCollection;
		
		///构造，参数可以为TreeNode、XML、XMLList
		public function TreeView(nodes:Object=null)
		{
			m_Nodes=new ArrayCollection();
			if(nodes!=null){
				if(nodes is TreeNode){
					m_Nodes.addItem(nodes);
				}
				else if(nodes is XML){
					this.createFromXML(nodes as XML);
				}else if(nodes is XMLList){
					this.createFromXMLList(nodes as XMLList);
				}
			}
		}
		//从XML构造
		private function createFromXML(xml:XML):void{
			if(xml.@text!=undefined || xml.text!=undefined||
				xml.@TEXT!=undefined || xml.TEXT!=undefined){
				m_Nodes.addItem(new TreeNode(xml));
			}else if(xml.children().length()>0){
				createFromXMLList(xml.children());
			}
		}
		//从XMLList构造
		private function createFromXMLList(xmlList:XMLList):void{
			if(xmlList.length()>0){
				for(var index:int=0; index
  
   length();index++){
					
   var xml:XML = xmlList[index];
					m_Nodes.addItem(
   new TreeNode(xml));
				}
			}
		}
		
		
   ///转换为XML
		
   public 
   function ToXML():XML{
			
   var xml:XML = 
   new XML("
   
    ");
			
   if(m_Nodes.
   length>0){
				
   for each(
   var node:TreeNode 
   in m_Nodes){
					xml.appendChild(node.ToXML());
				}
			}
			
   return xml;
		}
		
		
		
   static 
   public 
   function GetCheckedTreeNode(Data:XMLList):ArrayCollection{
			
   if(Data==
   null)
   return 
   null;
			
   var array:ArrayCollection = 
   new ArrayCollection();
			
   for(
   var index:
   int =0;index
   
    length();index++){ 
    var xNode:XML = Data.child(index)[0]; GetCheckedTreeNodeByNode(xNode,array); } 
    return array; } 
    static 
    private 
    function GetCheckedTreeNodeByNode(Node:XML,array:ArrayCollection):
    void{ 
    if(Node.@Checked=="
    true"){
    //本节点已经勾选 array.addItem(Node); } 
    if(Node.children().
    length()>0){
    //开始检测子节点 
    for(
    var index:
    int =0;index
    
     length();index++){ 
     var cNode:XML = Node.child(index)[0]; GetCheckedTreeNodeByNode(cNode,array); } } } } }