The following example shows how you can detect when the number of RadioButton objects changes in a RadioButtonGroup in Flex by listening for the numRadioButtonsChanged
event.
Full code after the jump.
<?xml version="1.0" encoding="utf-8"?> <!-- http://blog.flexexamples.com/2008/11/10/detecting-when-the-number-of-radio-buttons-changes-in-a-radio-button-group-in-flex/ --> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="vertical" verticalAlign="middle" backgroundColor="white" initialize="init();"> <mx:Script> <![CDATA[ import mx.controls.Alert; private function init():void { radioGroup.addEventListener("numRadioButtonsChanged", radioGroup_numRadioButtonsChanged); } private function radioGroup_numRadioButtonsChanged(evt:Event):void { var rb:RadioButton = radioGroup.getRadioButtonAt(radioGroup.numRadioButtons-1); var alert:Alert = Alert.show(evt.toString(), "label:" + rb.label); alert.status = "numRadioButtons:" + radioGroup.numRadioButtons; } ]]> </mx:Script> <mx:RadioButtonGroup id="radioGroup" /> <mx:HBox> <mx:RadioButton id="radioButton1" label="Red" group="{radioGroup}" /> <mx:RadioButton id="radioButton2" label="Orange" group="{radioGroup}" /> <mx:RadioButton id="radioButton3" label="Yellow" group="{radioGroup}" /> <mx:RadioButton id="radioButton4" label="Green" group="{radioGroup}" /> <mx:RadioButton id="radioButton5" label="Blue" group="{radioGroup}" /> </mx:HBox> </mx:Application>