iterator - Iterating a dataProvider in flex -

i'm wondering... want iterate through dataprovider, in component based on dropdownlist. first thing, didn't work (it compiled, never iterated), was:

var o:object; each (var o:object in dataprovider) { } 

i guess didn't work because ilist doesn't provide objects, or able explain easily.

i tried looks horrible efficiency perspective, nonetheless works. it:

for (var i:int = 0; < dataprovider.length; i++) {    o = dataprovider.getitemat(i); } 

but horrible felt tempted ask here possible solution.

update:

i'll try elaborate... i'm making (well, made already) component that, being dropdownlist, bindable, not index (like selectedindex="@{variable}"), value of variable inside of arraycollection.

say, have dataprovider 2 objects: {a:'5', nmb:'five', blabla:'cinco'} , {a:'39', nmb:'thirty-nine', blabla:'treinta y nueve'}.

this component, if declared this:

<com:ddlistn idxname="a" selectedn="@{val}" labelfield="nmb"> 

does use val set/get dropdownlist proper index, comparing value variable defined in idxname.

well, entire code (is not much):

<?xml version="1.0" encoding="utf-8"?> <s:dropdownlist xmlns:fx="http://ns.adobe.com/mxml/2009"                  xmlns:s="library://ns.adobe.com/flex/spark"                  xmlns:mx="library://ns.adobe.com/flex/mx"                 change="ch()">     <fx:declarations>     </fx:declarations>     <fx:script>         <![cdata[             private var _selectedn:string;              public var idxname:string = 'n';              [bindable(event="changeselected")]             public function selectedn():string             {                 return this.selecteditem[idxname];             }              public function set selectedn(v:string):void             {                 var o:object; //              each (var o:object in dataprovider) @@                 (var i:int = 0; < this.dataprovider.length; i++)                 {                     o = dataprovider.getitemat(i);                     if (o[idxname] == v)                     {                         this.selectedindex = i;                         _selectedn = v;                         dispatchevent(new event("changeselected"));                         return;                      }                  }                 this.selecteditem = null; // no seleccionar nada (@@?)                 _selectedn = null;                 dispatchevent(new event("changeselected"));             }              private function ch():void             {                 _selectedn = this.selecteditem[idxname];                 dispatchevent(new event("changeselected"));             }         ]]>     </fx:script> </s:dropdownlist> 

actually for each loops little bit slower normal for loops. take @ answer for vs foreach on array performance.

to answer question, why for each loop doesn`t work. unfortunatly type of loop works types of classes. far know are:

• array
• vector
• xml
• xmllist
• and classes extend proxy implement functions needed for each loops. listcollectionview , subclasses arraycollection , xmllistcollection ones know of.

collection classes arraylist not work for each loops since not native objects in flash player (like array) , don't extend proxy class.

so, best thing can use simple for loops , loops faster for each loops.