Спрятать/показать компонент можно таким образом:
Код:
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute">
<mx:WipeDown scaleYFrom="0" scaleYTo="1" target="{foo}" id="boo"/>
<mx:WipeUp scaleYFrom="1" scaleYTo="0" target="{foo}" id="moo"/>
<mx:Canvas id="foo" backgroundColor="0xFF6600" width="100" height="100" x="50" y="50" hideEffect="{boo}" showEffect="{moo}"/>
<mx:Button x="40" label="show" click="foo.visible=false" />
<mx:Button label="hide" click="foo.visible=true"/>
</mx:Application>