[flexcoders] Flex validator in action script

[Adnan]

Hello,

How can I represent the following validator in action script;

<mx:Validator 
    required="true" 
    source="{myText}" 
    />
<s:TextInput id="myText" />

I am starting with this;

    var textInput:TextInput = new TextInput();
    textInput.id = "myText";

    var val:Validator = new Validator();
    val.source = ;// problem how to define it to be bindable ?
    val.required = true;

Any ideas?