I am a total Flex noob (started off just a couple of days back). I have been assigned to create a drilldown effect for column and pie charts. Can you point me in the right direction, regarding the creation of a drilldown effect? It's ok if the thing doesnt have any fancy animations etc. I basically want to switch over to a new datasource depending which element in the chart was clicked. How do I identify which element was clicked and then how do I changed the datasource and redraw the chart?
Update: I implemented a basic solution that works by following this tutorial. Here is my code which is almost same as the provided sample.
<?xml version="1.0"?>
height="600">
<fx:Declarations>
<mx:SeriesSlide id="slideIn" duration="1000" direction="down"/>
<mx:SeriesSlide id="slideOut" duration="1000" direction="up"/>
</fx:Declarations>
<fx:Script><![CDATA[
import mx.collections.ArrayCollection;
import mx.charts.HitData;
import mx.charts.events.ChartItemEvent;
[Bindable]
private var profit04:ArrayCollection = new ArrayCollection([
{Month: "Jan", Profit: 2000},
{Month: "Feb", Profit: 1000},
{Month: "Mar", Profit: 1500}
]);
[Bindable]
private var profit05:ArrayCollection = new ArrayCollection([
{Month: "Jan", Profit: 2200},
{Month: "Feb", Profit: 1200},
{Month: "Mar", Profit: 1700},
{Month: "Apr", Profit: 700}
]);
[Bindable]
private var profit06:ArrayCollection = new ArrayCollection([
{Month: "Jan", Profit: 2400},
{Month: "Feb", Profit: 1400},
{Month: "Mar", Profit: 1900}
]);
[Bindable]
private var profit07:ArrayCollection = new ArrayCollection([
{Month: "Jan", Profit: 400},
{Month: "Feb", Profit: 1100},
{Month: "Mar", Profit: 1900},
{Month: "Apr", Profit: 1700},
{Month: "May", Profit: 2100}
]);
// level is a temporary variable used to determine when to drill down.
private var level:int = 1;
private function resultHandler():void {
dp = ArrayCollection(srv.lastResult.data.result);
}
private function zoomIntoSeries(e:ChartItemEvent):void {
if (level == 1) {
cs1.yField = "Profit";
cs1.xField = "Month";
if(e.hitData.chartItem.index==0)
{
chart.dataProvider=profit05;
cs1.dataProvider=profit05;
cs1.displayName = "2005";
p1.title = "2005 ";
}
else if(e.hitData.chartItem.index==1)
{
chart.dataPr开发者_开发知识库ovider=profit06;
cs1.dataProvider=profit06;
cs1.displayName = "2006";
p1.title = "2006 ";
}
else if(e.hitData.chartItem.index==2)
{
chart.dataProvider=profit07;
cs1.dataProvider=profit07;
cs1.displayName = "2007";
p1.title = "2007 ";
}
ca1.categoryField = "Month";
level = 2;
lbl1.text=e.hitData.chartItem.index.toString();
} else {
cs1.displayName = "2004";
cs1.yField = "Profit";
cs1.xField = "Month";
chart.dataProvider=profit04;
cs1.dataProvider=profit04;
ca1.categoryField = "Month";
p1.title = "2004 ";
// Add the Legend back to the Panel.
// Reset chart to original data provider.
level = 1;
lbl1.text=e.hitData.chartItem.index.toString();
}
}
]]></fx:Script>
<s:layout>
<s:VerticalLayout/>
</s:layout>
<s:Panel id="p1" title="2004">
<s:layout>
<s:VerticalLayout/>
</s:layout>
<mx:ColumnChart id="chart"
showDataTips="true"
itemClick="zoomIntoSeries(event)"
dataProvider="{profit04}">
<mx:series>
<mx:ColumnSeries id="cs1"
yField="Profit"
xField="Month"
displayName="2004"
dataProvider="{profit04}"
hideDataEffect="slideOut"
showDataEffect="slideIn"/>
</mx:series>
<mx:horizontalAxis>
<mx:CategoryAxis id="ca1" categoryField="Month"/>
</mx:horizontalAxis>
</mx:ColumnChart>
</s:Panel>
<s:Label fontSize="40" id="lbl1"/>
However, it feels rather clumsy and I am worried that in the real implementation with a fairly complex db, I am going to end up in trouble. Isn't there a more elegant/simpler/efficient solution?
Use the chartItemClick event: http://livedocs.adobe.com/flex/3/html/help.html?content=charts_eventsandeffects_11.html
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