Hi,

I am using a combo box and its dataprovider is an arrayCollection (dp1.arr1,
dp1 is a actionscript class and arr1 is a global arraycollection for class).
The data is refreshed every minute. Hence, in the dp1 class, refreshData()
method gets called every minute and populates a new arraycollection arr2 with
the data everytime. And then lastly arr1 points to arr2. (ie. in code I write
arr1=arr2). This works fine.

But the problem is say if I had selected "value 3" in combo box. Now when
data refreshes and arr1=arr2, the combobox shows "value 1" i.e the 1st value in
the array.

What I want is the data in the combo box should be refreshed every min. and
also the selected value should not change. The data is bound to change
everytime. i.e some values might be deleted and some new values might be added.

Can somebody please provide me with an example for this or provide a solution
to my above problem so that the seleceted value in combo box remains same?

This code should help. As soon as the app launches, select value3. If the new
array has gthe previously selected item, it will still be selected, otherwise
it will of course revert to the first item.

----- components/dp1.as -----
package components
{
import flash.events.TimerEvent;
import flash.utils.Timer;

import mx.collections.ArrayCollection;
import mx.controls.Alert;

public class dp1{
[Bindable] public var arr1:ArrayCollection = new ArrayCollection([
"value1", "value2", "value3"
]);
public var arr2:ArrayCollection = new ArrayCollection([
"value1", "value2", "value3", "value4", "value5", "value6"
]);
public var arr3:ArrayCollection = new ArrayCollection([
"value1", "value2"
]);
private var timer:Timer = new Timer(10000, 0);
private var cnt:uint = 1;

public function dp1(){
timer.addEventListener(TimerEvent.TIMER, timerHandler);
timer.start();
}

public function timerHandler(event:TimerEvent):void{
if(cnt++ % 3 == 0){
mx.controls.Alert.show("Switched to arr3, should NOT see value3.");
arr1 = arr3;
}else if(cnt++ % 2 == 0){
mx.controls.Alert.show("Switched to arr2, SHOULD see value3.");
arr1 = arr2;
}
arr1.refresh();
}
}
}
----------------------------------------------------------
----- ComboBoxController.mxml -----
<?xml version="1.0"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
creationComplete="init()">
<mx:Script>
<![CDATA[
import mx.controls.Alert;
import mx.collections.ArrayCollection;
import mx.events.CollectionEvent;
import components.dp1;
import mx.events.PropertyChangeEvent;
import mx.binding.utils.ChangeWatcher;

[Bindable] public var dp1:components.dp1 = new components.dp1();
[Bindable] private var cbxSelected:Object;
private var activityWatcher:ChangeWatcher;

private function init():void{
if(ChangeWatcher.canWatch(cbx, "dataProvider")){
activityWatcher = ChangeWatcher.watch( cbx, "dataProvider",
cbxDataProviderChangeHandler);
}
}

private function cbxDataProviderChangeHandler( event:CollectionEvent
):void{
var newDP:ArrayCollection = event.currentTarget.dataProvider as
ArrayCollection;
if(newDP.contains(cbxSelected)){
cbx.selectedIndex =
cbx.dataProvider.getItemIndex(cbxSelected.toString ());
}
}
]]>
</mx:Script>
<mx:ComboBox id="cbx" dataProvider="{dp1.arr1}"
change="cbxSelected=cbx.selectedItem"/>
</mx:Application>

I've already replied in flexcoders, please see my solution to this ComboBox problem:

http://mitek.id.au/blog/2008/10/28/c...ess-continues/

Cheers,
Dmitri.