Flex reset chart axis minimum/maximum

Question

Hi,

I am showing a stacked bar chart with Flex, and I am dynamically changing the data of the dataprovider.

However, the minimum and maximum for the y-axis do not get reset with the new data. So if one dataset had a value of -100,000, but the next dataset has only positive values, the y-axis still starts at -100,000.

How can I force the chart to redraw. I tried myChart.validateNow(), dataprovider.refresh(), etc.

 <mx:ColumnChart id="myChart"
     dataProvider="{_arrCol_chartData}"
     columnWidthRatio="0.8"
     type="stacked"
     width="100%"
     height="100%">
  <mx:annotationElements>
   <mx:CartesianDataCanvas id="canvas"
         includeInRanges="true"/>
  </mx:annotationElements>

  <mx:horizontalAxis>
   <mx:CategoryAxis dataProvider="{_arrCol_chartData}"
        categoryField="Month"
        id="a1"/>
  </mx:horizontalAxis>
  <mx:verticalAxisRenderers>
   <mx:AxisRenderer axis="{a1}"
        tickPlacement="none"
        showLabels="false"
        showLine="false"/>
  </mx:verticalAxisRenderers>

  <mx:series>
   <mx:ColumnSeries yField="invisible"
        displayName="invisible"
        showDataEffect="slideIn"
        hideDataEffect="slideOut">
    <mx:fill>
     <!--Set alpha to 0 to hide invisible column.-->
     <mx:SolidColor color="0xFFFFFF"
           alpha="0"/>
    </mx:fill>
   </mx:ColumnSeries>
   <mx:ColumnSeries yField="freeCashflow"
        styleName="standardSeries"
        labelFunction="setCurrencyLabel">
    <mx:fill>
     <mx:SolidColor color="0xCCCCCC"
           alpha="1"/>
    </mx:fill>
   </mx:ColumnSeries>
   <mx:ColumnSeries yField="invisibleTop"
        displayName="invisible"
        showDataEffect="slideIn"
        hideDataEffect="slideOut">
    <mx:fill>
     <!--Set alpha to 0 to hide invisible column.-->
     <mx:SolidColor color="0xFFFFFF"
           alpha="0"/>
    </mx:fill>
   </mx:ColumnSeries>
   <mx:ColumnSeries yField="bottom"
        styleName="standardSeries"
        labelFunction="setCurrencyLabel">

    <mx:fill>
     <mx:SolidColor color="0x1B95D5"
           alpha="1"/>
    </mx:fill>
   </mx:ColumnSeries>
   <mx:ColumnSeries yField="top"
        id="topColumn"
        styleName="standardSeries"
        labelFunction="setCurrencyLabel">
    <mx:fill>
     <mx:SolidColor color="0x00FF00"
           alpha="1"/>
    </mx:fill>
   </mx:ColumnSeries>
  </mx:series>
 </mx:ColumnChart>

[Bindable]  
private var _arrCol_chartData : ArrayCollection = new ArrayCollection([
   { ID: FREE_CASHFLOW, Month: "Free Cashflow", freeCashflow: 0, invisible: 0, invisibleTop: 5000 },
   { ID: CAPITAL_RESERVES, Month: "Capital Reserves", bottom: 0, invisible: 0 },
   { ID: REINVESTMENT_MONEY, Month: "Reinvestment Money", bottom: 0, invisible: 0 },
   { ID: PROFIT_SHARING, Month: "Profit Sharing", bottom: 0, invisible: 0 },
   { ID: DISTRIBUTABLE, Month: "Distributable", top: 0, invisible: 0 }]);


function changeDate() : void {
  _arrCol_chartData.getItemAt( 0 ).bottom = 1000;
  _arrCol_chartData.refresh();
}

Thx, Martin

Answer 1

This should do the job. `

a1.maximum = NaN;
a1.minimum = NaN; // or 0 if you want it based at zero{

`

edit:

I changed the code to look like this:

<mx:horizontalAxis>
    <mx:CategoryAxis dataProvider="{_arrCol_chartData}"
        categoryField="Month"
        id="a1"/>
</mx:horizontalAxis>
<mx:horizontalAxisRenderers>
<mx:AxisRenderer axis="{a1}"
    tickPlacement="none"
    showLabels="true"
    showLine="false"/>
</mx:horizontalAxisRenderers>

and the linear axis updated perfectly.

Answer 2

This is a known Bug in Flex Charting when using "stacked" setting.

https://bugs.adobe.com/jira/browse/FLEXDMV-1674