HTTPService not firing ResultHandler (maybe)

Question

In my custom FileInfo panel I've got an HTTPService that works sends and receives data perfectly when a button triggers the function (click= "lookup1()").
When I use xmpRead="lookup1()" it sends, but doesn't return any data..... but when I click on another FileInfo panel and back again, the returned data is there!
Any idea why the resultHandler doesn't run until told to or the page RE-loads?
Thanks,
Alex

Answer 1

Okay, so I've gleaned from other Forum discussions what might be a possible reason for my problem.
I think that when the xmpRead event happens, my lookup_1Result() resultHandler returns its results but doesn't have a place to put them because the comboBox page element it populates isn't finished being drawn when the dataProvider is assigned. By clicking to another panel and back, the page doesn't completely recreate the panel, it just updates the objects. By changing the xmpRead() to creationComplete() [which I thought I tried already and had no success], the resultHandler returns its results after there is a place for everything. 
<fi:XMPForm
xmlns:mx="http://www.adobe.com/2006/mxml"
xmlns:fi="com.adobe.xmp.components.*" width="100%" height="100%"
label="VCS_PGL_1_2" xmpRead="lookup1()" creationComplete="lookup1()">
<mx:Script>
<![CDATA[
private function lookup_1Result(event:ResultEvent):void {
var list_1String:String = new String;
var list_1Array:Array = new Array;
list_1String = lookup_1.lastResult.toString();     //copies the response to the HTTPService lookup to the string variable
list_1Array = list_1String.split(hardReturn);        //splits the string at the hard returns, copies to the Array
comboBox_1.dataProvider = list_1Array; }          //assigns the array to the drop down
]]>
</mx:Script>
<mx:comboBox id="comboBox_1" />