Bind tooltip text value to a TextInput
<?xml version="1.0" encoding="utf-8"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"> <mx:VBox> <mx:Button id="button" label="Button" toolTip="{textInput.text}" /> <mx:TextInput id="textInput" /> </mx:VBox> </mx:Application>