Flex：Tree中自定义ICON的几种方式

1、默认的Tree的属性是文件夹和文件都是通过 folderOpenIcon, folderClosedIcon,and defaultLeafIcon 来执行的，如果在程序中需要取得默认的参数可以通过这几个参数进行处理

????var myMenu:SysMenu = SysMenu(item);
????if(myMenu.children.length==0){
?????return leftMenuTree.getStyle("defaultLeafIcon");
????}
????if ( leftMenuTree.isItemOpen(item) ) {
???????? ???return leftMenuTree.getStyle("folderOpenIcon");
????? ???} else {
???????? ???return leftMenuTree.getStyle("folderClosedIcon");
????? ???}

当然也可以直接通过flex的标签来制定

<mx:Tree folderOpenIcon="@Embed(source='open.jpg')"folderClosedIcon="@Embed(source='closed.jpg')"defaultLeafIcon="@Embed(source='def.jpg')">

?

2、通过data provider来提供数据源的时候就指定icon

<mx:XMLList>
???????? <node label="New">
??????????? <node label="HTML Document" icon="iconSymbol2"/>
??????????? <node label="Text Document" icon="iconSymbol2"/>
???????? </node>
???????? <node label="Close" icon="iconSymbol1"/>
????? </mx:XMLList>

?

3、通过函数setItemItcon

???????? [Bindable]
???????? [Embed(source="assets/radioIcon.jpg")]
???????? public var iconSymbol1:Class;
???????? [Bindable]
???????? [Embed(source="assets/topIcon.jpg")]
???????? public var iconSymbol2:Class;
????????
???????? private function setIcons():void {
??????????? myTree.setItemIcon(myTree.dataProvider.getItemAt(0),
?????????????? iconSymbol1,iconSymbol2);
??????????? myTree.setItemIcon(myTree.dataProvider.getItemAt(1),
?????????????? iconSymbol2,null);
???????? }

4、Tree支持显示icon的属性iconFunction ，自定义处理函数就可以了，示例如下

<?xml?version="1.0"?encoding="utf-8"?>
<!--?http://yecon.blog.hexun.com/30744073_d.html?-->
<mx:Application?xmlns:mx="http://www.adobe.com/2006/mxml"
????????layout="vertical"
????????verticalAlign="middle"
????????backgroundColor="white">

????<mx:Script>
????????<![CDATA[
????????????[Bindable]
????????????[Embed("assets/bullet_go.png")]
????????????private?var?myBulletGoIcon:Class;

????????????[Bindable]
????????????[Embed("assets/bullet_star.png")]
????????????private?var?myBulletStarIcon:Class;

????????????[Bindable]
????????????[Embed("assets/bullet_wrench.png")]
????????????private?var?myBulletWrenchIcon:Class;

????????????private?function?tree_iconFunc(item:Object):Class?{
????????????????var?iconClass:Class;
????????????????switch?(XML(item).localName())?{
????????????????????case?"league":
????????????????????????iconClass?=?myBulletGoIcon;
????????????????????????break;
????????????????????case?"division":
????????????????????????iconClass?=?myBulletStarIcon;
????????????????????????break;
????????????????????case?"team":
????????????????????????iconClass?=?myBulletWrenchIcon;
????????????????????????break;
????????????????}
????????????????return?iconClass;
????????????}
????????]]>
????</mx:Script>

????<mx:XML?id="dp">
????????<mlb>
????????????<league?label="American?League">
????????????????<division?label="East">
????????????????????<team?label="Boston"?/>
????????????????????<team?label="New?York"?/>
????????????????????<team?label="Toronto"?/>
????????????????????<team?label="Baltimore"?/>
????????????????????<team?label="Tampa?Bay"?/>
????????????????</division>
????????????????<division?label="Central">
????????????????????<team?label="Cleveland"?/>
????????????????????<team?label="Detroit"?/>
????????????????????<team?label="Minnesota"?/>
????????????????????<team?label="Chicago"?/>
????????????????????<team?label="Kansas?City"?/>
????????????????</division>
????????????????<division?label="West">
????????????????????<team?label="Los?Angeles"?/>
????????????????????<team?label="Seattle"?/>
????????????????????<team?label="Oakland"?/>
????????????????????<team?label="Texas"?/>
????????????????</division>
????????????</league>
????????</mlb>
????</mx:XML>

????<mx:Tree?id="TreeProject"
????????????dataProvider="{dp.league}"
????????????labelField="@label"
????????????showRoot="true"
????????????iconFunction="tree_iconFunc"
????????????width="320"
????????????height="240"?/>

</mx:Application>