Flash builder 4 (beta 2) dropdown attributes different?? and differences between beta 1 and 2

Question

hey guys, i had everything working before just fine, but in this beta 2, my drop down lists are not working... i realised that previously the attribute requiresSelection in the dropdownlist tag of beta 1, is now "requireSelection" and it is giving me an error on selectionChanged...
i was wondering if there is somehitng i could use other than selectionChanged??
and also, does anyone know where i can find all the differences from Beta 1, and Beta2??

Answer 1

Actually, the requiresSelection was renamed to requireSelection:
<?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">
    <fx:Script>
        <![CDATA[
            import mx.controls.Alert;
            import spark.events.IndexChangeEvent;
            protected function ddl_changeHandler(evt:IndexChangeEvent):void {
                Alert.show("oldIndex:" + evt.oldIndex + ", newIndex:" + evt.newIndex, evt.type);
            protected function ddl_changingHandler(evt:IndexChangeEvent):void {
                Alert.show("oldIndex:" + evt.oldIndex + ", newIndex:" + evt.newIndex, evt.type);
        ]]>
    </fx:Script>
    <s:DropDownList id="ddl"
                    requireSelection="true"
                    change="ddl_changeHandler(event);"
                    changing="ddl_changingHandler(event)">
        <s:dataProvider>
            <s:ArrayList source="[One,Two,Three,Four,Five,Six,Seven,Eight,Nine,Ten]" />
        </s:dataProvider>
    </s:DropDownList>
</s:Application>
Peter