Set pie slice color

Question

Hey guys,
         I am creating pie chart based on xml data, which can have at most 6 categories, but not every time.  For consistency sake I would like pie slice to be colored by category, i.e every time I see category 1 it should be colored with c1, category 2 should be colored c2 etc.  By just setting fill property I don't always get the same color for category 2 if category 1 is missing. 
     Hope my objective is clear, does anyone have any idea, I have been nosing around adobe forms and google but no luck so far.
Thank you
Jay

Answer 1

Instead of a switch statement you could do this, the colors use the fieldname as id's so you then have a single line in your fillfunction.
<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/halo" minWidth="1024" minHeight="768" xmlns:local="*">
<fx:Declarations>
<s:SolidColor id="Taxes" color="blue" alpha="1"/>
<s:SolidColor id="Rent" color="red" alpha="1"/>
<s:SolidColor id="Bills" color="green" alpha="1"/>
<s:SolidColor id="Car" color="gray" alpha="1"/>
<s:SolidColor id="Gas" color="black" alpha="1"/>
<s:SolidColor id="Food" color="yellow" alpha="1"/>
</fx:Declarations>
<fx:Script>
<![CDATA[
import mx.charts.series.items.PieSeriesItem;
import mx.graphics.IFill;
import mx.charts.ChartItem;
import mx.collections.ArrayCollection;
[Bindable]
public var expenses:ArrayCollection = new ArrayCollection([
{Expense:"Taxes", Amount:2000},
{Expense:"Rent", Amount:1000},
{Expense:"Bills", Amount:100},
{Expense:"Car", Amount:450},
{Expense:"Gas", Amount:100},
{Expense:"Food", Amount:200}
private function myFiller(item:ChartItem, index:Number):IFill
return(this[expenses[index].Expense]);
]]>
</fx:Script>
<mx:Panel title="Pie Chart">
<mx:PieChart id="myChart"
dataProvider="{expenses}"
showDataTips="true"
innerRadius=".3"
>
<mx:series>
<mx:PieSeries
field="Amount"
nameField="Expense"
    fillFunction="myFiller"
/>
</mx:series>
</mx:PieChart>
</mx:Panel>
</s:Application>