I am not able to access it.
Why do you need to access it? What do you want to do with button when accessed?You can listen button events. For example:1 - Modified esri sample application
<?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/mx"
xmlns:esri="http://www.esri.com/2008/ags"
pageTitle="FeatureLayer on demand">
<!--
This sample shows you how to add InfoWindows to a feature layer.
When user clicks on one of the polygon features, the info window popup will show.
-->
<s:layout>
<s:VerticalLayout/>
</s:layout>
<fx:Style>
@namespace s "library://ns.adobe.com/flex/spark";
@namespace mx "library://ns.adobe.com/flex/mx";
@namespace esri "http://www.esri.com/2008/ags";
esri|InfoWindow
{
skin-class: ClassReference("your.path.to.InfoWindowSkin");
}
</fx:Style>
<fx:Script>
<![CDATA[
import mx.controls.Alert;
import mx.events.FlexEvent;
protected function map1_creationCompleteHandler(event:FlexEvent):void
{
if (map.infoWindow)
{
map.infoWindow.addEventListener("onSubmitClick", onInfoWindowSubmitClick, false, 0, true);
}
}
protected function onInfoWindowSubmitClick(event:Event):void
{
Alert.show("submit button clicked", "! ! !");
}
]]>
</fx:Script>
<esri:Map id="map"
openHandCursorVisible="false"
creationComplete="map1_creationCompleteHandler(event)">
<esri:extent>
<!-- Extent for Bloomfield Hills, Michigan -->
<esri:Extent xmin="-9271300" ymin="5247400" xmax="-9270300" ymax="5248500">
<esri:SpatialReference wkid="102100"/>
</esri:Extent>
</esri:extent>
<esri:ArcGISTiledMapServiceLayer url="http://server.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer"/>
<esri:FeatureLayer id="fLayer"
mode="onDemand"
outFields="[PARCELID,OWNERNME1,SITEADDRESS,LNDVALUE,USECD]"
url="http://sampleserver3.arcgisonline.com/ArcGIS/rest/services/BloomfieldHillsMichigan/Parcels/MapServer...">
<esri:symbol>
<esri:SimpleFillSymbol id="fillsym" style="null">
<esri:SimpleLineSymbol width="3" color="0xFF0000"/>
</esri:SimpleFillSymbol>
</esri:symbol>
<esri:infoWindowRenderer>
<fx:Component>
<mx:VBox backgroundColor="0xffffff"
color="0x444444"
label="Parcel {data.PARCELID}">
<mx:Label text="Owner: {data.OWNERNME1}"/>
<mx:Label text="Address: {data.SITEADDRESS}"/>
<mx:Label text="Land Value: {data.LNDVALUE}"/>
<mx:Label text="Landuse: {data.USECD}"/>
</mx:VBox>
</fx:Component>
</esri:infoWindowRenderer>
</esri:FeatureLayer>
</esri:Map>
<s:Label enabled="{fLayer.loaded}" text="Using the 'onDemand' mode, parcels are fetched 'as needed' when you pan and zoom. Click any parcel to see more information."/>
</s:Application>
2 - Modifications in InfoWindowSkin
<fx:Metadata>
/**
* A strongly typed property that references the component to which this skin is applied.
*/
[HostComponent("com.esri.ags.components.supportClasses.InfoWindow")]
[Event(name="onSubmitClick", type="flash.events.Event")]
</fx:Metadata>
...
<fx:Script>
<![CDATA[
/**
* Listen submit button click
*/
protected function onSubmitButtonClick(event:MouseEvent):void
{
dispatchEvent(new Event("onSubmitClick", true, false));
}
]]>
</fx:Script>
...
<s:HGroup id="headerGroup"
width="100%"
includeInLayout.withoutHeader="false"
minWidth="0"
verticalAlign="middle"
visible.withoutHeader="false">
<esri:InfoWindowLabel id="labelText"/>
<s:Rect width="100%" height="10"
minWidth="0"/>
<esri:InfoWindowCloseButton id="closeButton"/>
<s:Button id="submitButton"
click="onSubmitButtonClick(event)"
label="Submit"/>
