flex 改变linechart datatips 显示样式代码

这是flex文件mxml的一个sample，是关于linechart这个控件的

以及弹出datatip中字体大小的控制，但仅限于字体，其他样式颜色并不能改变

<?xml version="1.0" encoding="utf-8"?>

<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="vertical"
        verticalAlign="middle"
        backgroundColor="white" >
<mx:Style source="css/default.css" />
   <mx:Script>
        <![CDATA[
            import mx.styles.StyleManager;       
            import legendfont;           
            import mx.charts.HitData; 
            import mx.charts.series.items.LineSeriesItem;
            
             private function pieChart_dataTipFunction(item:HitData):String { 
                var LCI:LineSeriesItem = item.chartItem as LineSeriesItem; 
                return "<font size='19'><b><i>"+ LCI.yValue+ "</i></b><br />" + 
                       LCI.item.@date+ "</b><br/></font>"; 
            }

          //改变datatip字体大小
        ]]>
    </mx:Script>
    <mx:XMLListCollection > 
             </mx:series>

                //关于linechart中线条的颜色样式
           
         </mx:LineChart>
    <mx:Legend dataProvider="{lineChart1}" direction="horizontal" height="28" legendItemClass="legendfont" />
    </mx:Panel>

    <mx:ApplicationControlBar dock="true">
        <mx:Button label="0xFF0000" click="closeSeries.setStyle(&apos;lineStroke&apos;, new Stroke(0xFF0000, 2, 0.4));" />
        <mx:Button label="0xFF00FF" click="closeSeries.setStyle(&apos;lineStroke&apos;, new Stroke(0xFF00FF, 2, 1.0));" />
        <mx:Button label="haloSilver" click="closeSeries.setStyle(&apos;lineStroke&apos;, new Stroke(StyleManager.getColorName(&apos;haloSilver&apos;), 2, 1.0));" />

        <mx:Spacer width="100%" />
    </mx:ApplicationControlBar>
    
     
    
</mx:Application>

来自: http://hi.baidu.com/%B2%D0%C7%EF%BF%D5%CA%C5/blog/item/786a5ad72a90c32606088bb8.html