Auto-generated itemrenderer has an error

[Blkhwks19]

Im loading in some XML data into a Spark DataGrid. Everything works properly. Now I want to add a custom itemrenderer to one of the columns. I have Flash Builder auto-generate the itemrenderer and simply run the code, but the custom item renderer throws an error. Here's all the code Im working with:

Main.mxml:

<?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" minWidth="955" minHeight="600" creationComplete="creationCompleteHandler(event)">
	
	<fx:Declarations>
		<s:HTTPService id="service" url="data.xml" resultFormat="e4x" result="resultHandler(event)" fault="faultHandler(event)"/> 
	</fx:Declarations>
	
	<fx:Script>
		<![CDATA[
			import mx.collections.XMLListCollection;
			import mx.controls.Alert;
			import spark.components.gridClasses.GridColumn;
			import mx.events.FlexEvent;
			import mx.rpc.events.FaultEvent;
			import mx.rpc.events.ResultEvent;
			
			private var xml:XML;
			private var xmlList:XMLList;
			private var xmlListColl:XMLListCollection
						
			protected function creationCompleteHandler(event:FlexEvent):void
			{
				service.send();
			}
			
			protected function resultHandler(event:ResultEvent):void
			{
				xml = event.result as XML;
				xmlList = new XMLList(xml);
				xmlListColl = new XMLListCollection(xmlList.game);
				dg.dataProvider = xmlListColl;
			}
						
			protected function faultHandler(event:FaultEvent):void
			{
				trace("There was an error loading the XML.");
			}
			
		]]>
	</fx:Script>
	
	<s:DataGrid id="dg" width="500" rowHeight="30">
		<s:columns>
			<s:ArrayList>
				<s:GridColumn headerText="Col1" dataField="@attr1"/>
				<s:GridColumn headerText="Col2" dataField="@attr2"/>
				<s:GridColumn headerText="Col3" dataField="@attr3"/>
				<s:GridColumn headerText="Col4" dataField="@attr4" itemRenderer="CustomRenderer"/>
                       </s:ArrayList>
		</s:columns>
	</s:DataGrid>
</s:Application>

CustomRenderer.mxml:

<?xml version="1.0" encoding="utf-8"?>
<s:GridItemRenderer xmlns:fx="http://ns.adobe.com/mxml/2009" 
					xmlns:s="library://ns.adobe.com/flex/spark" 
					xmlns:mx="library://ns.adobe.com/flex/mx" clipAndEnableScrolling="true">
	
	<fx:Script>
		<![CDATA[
			override public function prepare(hasBeenRecycled:Boolean):void {
				lblData.text = data[column.dataField]
			}
		]]>
	</fx:Script>
	
	<s:Label id="lblData" top="9" left="7"/>
	
</s:GridItemRenderer>

data.xml:

<items> 
	<item attr1="attr1" attr2="attr2" attr3="attr3" attr4="attr4" />
        <item attr1="attr1" attr2="attr2" attr3="attr3" attr4="attr4" />
        <item attr1="attr1" attr2="attr2" attr3="attr3" attr4="attr4" />
        <item attr1="attr1" attr2="attr2" attr3="attr3" attr4="attr4" />
        <item attr1="attr1" attr2="attr2" attr3="attr3" attr4="attr4" />
</items>

So to recap, Flash Builder is generating the custom item renderer code. I didnt write anything in that class. The error thats thrown is saying that the 'data' object is null. Not sure why this is. I should be able to say data[column.dataField] or data.@attr4 to get to my data, but it keeps saying data is null.

Also, I'm using Flash Builder 4.5 with the 4.5.1 sdk. All my components are Spark components, I try to avoid MX as much as possible.

Any thoughts on whats going on or how to fix it? Thanks! :-)

[ASWC]

you are setting your array list with data that does not exist. Also even though you are not showing the error, from what you are saying there's no connection with the error and the ItemRenderer. The fact that the ItemRenderer can't find the data doesn't mean it's a problem with the ItemRenderer. You have it backward here.

[Blkhwks19]

Ok that makes sense. So it seems the itemrenderer is trying to access the data before its been fully retrieved and is available, thus the reason Im getting the null error.

If thats the case, then how do i make the itemrenderer wait until the data is available before it does its thing? is there a way to "activate" the itemrenderer once the dataprovider is set, or something like that?

[Blkhwks19]

Figured out how to set the itemrenderer in AS, but any way to do it in MXML?

[Blkhwks19]

Still curious about this if anyone has any thoughts.....

[ASWC]

About what?

[Blkhwks19]

Well I was able to accomplish what I needed in Actionscript, but I'm curious if there's a way to do the same thing via MXML. Like an attribute on a tag or something like that.

[Yui]

Originally Posted by Blkhwks19

how do i make the itemrenderer wait until the data is available before it does its thing?

you don't have to wait.. you can check if the data is available:

override public function prepare(hasBeenRecycled:Boolean):void {
                if (data) {
                       lblData.text = data[column.dataField]
                       }
            }

as for inline itemRenderers: http://livedocs.adobe.com/flex/3/htm...enderer_6.html

[Syllogism]

Why don't you rather overwrite set data and set you values there. Also, remember to call the super() too.