Use a similar technique to add data series to your charts rather than replacing the existing ones

           
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<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml">
  <mx:Script>
    import mx.collections.ArrayCollection;
    import mx.charts.series.ColumnSeries;
    [Bindable]
    public var profit04:ArrayCollection = new ArrayCollection([
      {Month: "Jan", Profit: 2000},
      {Month: "Feb", Profit: 1000},
      {Month: "Mar", Profit: 1500}
      ]);
    [Bindable]
    public var profit05:ArrayCollection = new ArrayCollection([
      {Month: "Jan", Profit: 2200},
      {Month: "Feb", Profit: 1200},
      {Month: "Mar", Profit: 1700}
      ]);
    [Bindable]
    public var profit06:ArrayCollection = new ArrayCollection([
      {Month: "Jan", Profit: 2400},
      {Month: "Feb", Profit: 1400},
      {Month: "Mar", Profit: 1900}
      ]);
    public var series1:ColumnSeries;
    public var series2:ColumnSeries;
    public function addMoreSeries():void {
      if (!series1 || !series2) {
        series1 = new ColumnSeries();
        series1.dataProvider = profit05;
        series1.yField = "Profit";
        series1.xField = "Month";
        series1.displayName = "2005";
        series2 = new ColumnSeries();
        series2.dataProvider = profit06;
        series2.yField = "Profit";
        series2.xField = "Month";
        series2.displayName = "2006";
        var currentSeries:Array = myChart.series;
        currentSeries.push(series1);
        currentSeries.push(series2);
        myChart.series = currentSeries;
      }
    }
    </mx:Script>
  <mx:Panel title="Column Chart">
    <mx:ColumnChart id="myChart" dataProvider="{profit04}">
      <mx:horizontalAxis>
        <mx:CategoryAxis categoryField="Month" />
      </mx:horizontalAxis>
      <mx:series>
        <mx:ColumnSeries dataProvider="{profit04}"
          yField="Profit" xField="Month" displayName="2004" />
      </mx:series>
    </mx:ColumnChart>
    <mx:Legend dataProvider="{myChart}" />
  </mx:Panel>
  <mx:Button id="b1" label="Add More Series To Chart"
    click="addMoreSeries()" />
</mx:Application>

Related examples in the same category

1.	ColumnChart with ColumnSeries
2.	Use the fill property to set the color for each ColumnSeries object in a ColumnChart control
3.	Define a custom SolidColor object and a custom SolidColorStroke object, and applies them to the ColumnSeries object in the ColumnChart control.
4.	The following example mixes a LineSeries and a ColumnSeries
5.	The following example defines the colors for two series in the ColumnChart control:
6.	Adding Series to ColumnChart
7.	defines the colors for two series in the ColumnChart control
8.	Create a ColumnChart control with two series
9.	Data Update In Real Time Series
10.	uses two series to allow a visual comparison of two stocks that trade in different ranges
11.	Cast the HitData object to a Series class
12.	Set elementOffset property of SeriesInterpolate to 0.
13.	Increments and decrements the series's selectedIndex property to select each item
14.	Add or remove a data point from a series in ActionScript.
15.	yValue of the ColumnSeriesItem represents the percentage a series takes up in a 100% chart
16.	Use chart items in more than one series
17.	Zoom in data series from the upper-right corner of the chart.
18.	Change fields of a series to change chart data at run time
19.	The final result is a chart with multiple axes, but whose series share some of the same properties defined by common axis renderers.

Use a similar technique to add data series to your charts rather than replacing the existing ones : Column Chart ColumnSeries « Chart « Flex

Related examples in the same category