<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="vertical">
<mx:Form>
<mx:FormItem label="Start Date">
<mx:DateField id="startDate" change="update(event)"/>
</mx:FormItem>
<mx:FormItem label="End Date">
<mx:DateChooser id="endDate" change="update(event)"/>
</mx:FormItem>
<mx:FormItem label="Trip Duration (days)">
<mx:Label id="display"/>
</mx:FormItem>
</mx:Form>
<mx:Script>
import mx.events.CalendarLayoutChangeEvent;
private function update(evt:CalendarLayoutChangeEvent):void {
var MILLISECONDS:int = 1000;
var SECONDS:int = 60;
var MINUTES:int = 60;
var HOURS:int = 24;
var diff:Number = endDate.selectedDate.getTime() - startDate.selectedDate.getTime();
var days:int = int(diff/(MILLISECONDS*SECONDS*MINUTES*HOURS));
display.text = days.toString();
}
</mx:Script>
</mx:Application>
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