Flex 中树的多种操作(可编辑，拖拽，新增删除等操作)

<?xml version="1.0" encoding="utf-8"?>
<mx:Canvas xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx" width="400" height="300" creationComplete="init();">
<fx:Declarations>
<!-- 将非可视元素（例如服务、值对象）放在此处 -->
<mx:XMLListCollection id="datatree" source="{_xmldata.children()}" />
</fx:Declarations>


<fx:Script>
<![CDATA[
import mx.controls.treeClasses.TreeItemRenderer;
import mx.controls.listClasses.ListItemRenderer;
import mx.events.ItemClickEvent;
import mx.states.AddChild;
import mx.controls.Alert;
import flash.events.MouseEvent;

import mx.controls.listClasses.IListItemRenderer;

private var xml:XML;
private var MNum:int = 8;
private var ANum:int = 0;
[Bindable]
private var _xmldata:XML =
<stage>
<AllNode id="1" label="总节点1">
<Node id="2" label="子节点"></Node>
<Node id="3" label="子节"></Node>
<Node id="4" label="子"></Node>
</AllNode>
<AllNode id="5" label="总节点2">
<Node id="6" label="子节点2"></Node>
<Node id="7" label="子节2"></Node>
<Node id="8" label="子2"></Node>
</AllNode>
</stage>




private var createMenu: ContextMenuItem;
private var deleteMenu: ContextMenuItem;
private var renameMenu: ContextMenuItem;


internal function init(): void{
treeMenu();
xml = _xmldata;
tree.addEventListener(ListEvent.ITEM_EDIT_END, itemEditEndHandler);
tree.addEventListener(ListEvent.ITEM_EDIT_BEGINNING, itemEditBeginHandler);
}

private function itemEditBeginHandler(event: ListEvent): void{
var targetTree: Tree = Tree(event.target);
var item:XML = new XML(targetTree.selectedItem);
if(item.@editabled == "false"){
event.preventDefault();
}
}


private function itemEditEndHandler(event:ListEvent):void
{
tree.editable = false;
}

//用event.currentTarget.itemEditorInstance.text得到编辑后的内容

//这个方法在那个是不成功，自己重写了一个
/*
public function itemEditEndHandler(event:ListEvent):void {
event.preventDefault();
var newValue:String = event.currentTarget.itemEditorInstance.text;
trace("newValue:"+newValue);

tree.editedItemRenderer.data.@name = newValue;
tree.destroyItemEditor();
}
*/

private function treeMenu(): void{
createTreeMenuItem();
tree.contextMenu = getTreeContxtMenu();
}

public function createTreeMenuItem(): void{
createMenu = new ContextMenuItem("新建");
deleteMenu = new ContextMenuItem("de22");
renameMenu = new ContextMenuItem("重命名");
createMenu.addEventListener(ContextMenuEvent.MENU_ITEM_SELECT, createNode);
deleteMenu.addEventListener(ContextMenuEvent.MENU_ITEM_SELECT, deleteNode);
renameMenu.addEventListener(ContextMenuEvent.MENU_ITEM_SELECT, renameNode);
}


private function getTreeContxtMenu(): ContextMenu{
var contextMenu: ContextMenu = new ContextMenu();
contextMenu.hideBuiltInItems();
contextMenu.customItems.push(createMenu);
contextMenu.customItems.push(deleteMenu);
contextMenu.customItems.push(renameMenu);
return contextMenu;
}


private function createNode(event:ContextMenuEvent):void{

var item:Object = onRightClicked(event);

if (item != null) {

if( xml == null ) return;

if( xml.length() > 0 )
{

//关闭节点，如果不这样做，会有问题
item = tree.selectedItem;
if (tree.dataDescriptor.isBranch(item) && tree.isItemOpen(item)) {
tree.expandItem(item, false);
}

ANum ++;
var nodeId: int = MNum + 1;


//添加新节点
var nodeString:String = "<Node id=\""+nodeId+"\" label=\""+"新节点"+"\" ></Node>";
var _XML:XML = new XML(nodeString);

_XML.@label = "新节点"+ANum;
(item as XML).appendChild(_XML);


//展开该节点
item = tree.selectedItem;
if (tree.dataDescriptor.isBranch(item) && !tree.isItemOpen(item)) {
tree.expandItem(item, true);
}

//定位到新节点
var children:XMLList = XMLList(item as XML).children();

for(var i:Number=0; i < children.length(); i++) {

if( children[i].@label == _XML.@label ) {

var newItemRender:IListItemRenderer;

var newNodeIndex:int;

tree.visible = true;

tree.firstVisibleItem = children[i] as Object;

//这句定位要求，是树中可见的节点中定位
newItemRender = tree.itemToItemRenderer(children[i] as Object);

if(newItemRender != null) {

newNodeIndex = tree.itemRendererToIndex(newItemRender);

if(tree.selectedIndex != newNodeIndex) {

tree.selectedIndex = newNodeIndex;

tree.editable = true;

tree.editedItemPosition = {rowIndex: tree.selectedIndex};

}

}else{
tree.selectedItem = children[i] as Object;

tree.editable = true;

tree.editedItemPosition = {rowIndex: tree.selectedIndex};
}

//如果不加这几句，有时候就不好使啊！被迫加上了，以后有改进的办法了再说吧
tree.firstVisibleItem = children[i] as Object;

tree.selectedItem = children[i] as Object;

tree.editable = true;

tree.editedItemPosition = {rowIndex: tree.selectedIndex};

break;
}
}
MNum++;


}
}
else return;
}


private function deleteNode(event:ContextMenuEvent):void{

var item:Object = onRightClicked(event);

if (item != null) {

if( xml == null ) return;

if( xml.length() > 0 )
{
tree.dataDescriptor.removeChildAt(

tree.selectedItem.parent(),

tree.selectedItem,

tree.selectedItem.childIndex(),

tree.dataProvider

);
}
}
else return;

}

private function renameNode(event:ContextMenuEvent):void{

var item:Object = onRightClicked(event);

if (item != null) {

if( xml == null ) return;
if( xml.length() > 0 )
{
tree.editable = true;
tree.editedItemPosition = {rowIndex: tree.selectedIndex};
}
}
else return;
}

//右键定位节点
private function onRightClicked(e:ContextMenuEvent):Object

{

var rightClickItemRender:IListItemRenderer;

var rightClickIndex:int;

if(e.mouseTarget is IListItemRenderer) {

rightClickItemRender = IListItemRenderer(e.mouseTarget);

}else if(e.mouseTarget.parent is IListItemRenderer) {

rightClickItemRender = IListItemRenderer(e.mouseTarget.parent);

}


if(rightClickItemRender != null) {

rightClickIndex = tree.itemRendererToIndex(rightClickItemRender);

if(tree.selectedIndex != rightClickIndex) {

tree.selectedIndex = rightClickIndex;

}
trace("通过右键单击获得选定的行: " + tree.selectedIndex);

}

//树节点的xml
var globalItem:Object = tree.selectedItem;

if(globalItem != null){

var node:XML = (globalItem as XML)

trace("通过右键单击获得选定的行: " + node.@id +",node.label:"+ node.@label);


if (node.@id != undefined)

return globalItem;

else{

Alert.show("此节点不可操作");

return null;

}
}
return null;

}

import mx.collections.ICollectionView;

import mx.events.ListEvent;


//鉴于单击收缩功能可能影响到右键操作，所以废除了
private function tree_itemClick(evt:ListEvent):void {

var item:Object = Tree(evt.currentTarget).selectedItem;

if (tree.dataDescriptor.isBranch(item)) {

tree.expandItem(item, !tree.isItemOpen(item), true);

}

}

/******变换选中的tree节点事件，透过这个改变xml，该方法必须有********/
private function treeChange(e:Event):void
{
xml = e.currentTarget.selectedItem as XML;
}

private function tree_itemDoubleClick(event: ListEvent):void{

var node:XML = tree.selectedItem as XML;
var isOpen:Boolean = tree.isItemOpen(node);
tree.expandItem(node, !isOpen);
}

private function doubleClickHandler(event:MouseEvent):void
{
tree.editable = true;
tree.editedItemPosition = {rowIndex: tree.selectedIndex};
}

]]>
</fx:Script>

<!-- doubleClickEnabled="true"
itemDoubleClick="tree_itemDoubleClick(event);" -->


<mx:Tree id="tree"
width="100%"
height="100%"
fontFamily="Arial"
fontSize="12"
textAlign="left"
dataProvider="{datatree}"
labelField="@label"
change="treeChange(event)"
rowCount="10"
doubleClickEnabled="true"
doubleClick="doubleClickHandler(event)"
itemEditEnd="itemEditEndHandler(event)"
dragEnabled="true"
dropEnabled="true"
/>

</mx:Canvas>