[Arp] Dispatch event or internal ?

[Davies, Grant M.]

Hi guys, have a fairly simple design question but wanted to see the best way
of implementing this using ARP.

I have a loginForm that has a id, password and button, I catch the id -
changed event and the password changed event so that the login button is
grayed out when those fields are not valid, I have strict validation that
the id must be 5 characters or more (RACF security) and the password must be
exactly 8 characters.

What I was wondering is should I keep to booleans in my LoginFrom class 

var idValid:Boolean;
var passwordValid:Boolean;

and when catch the change event for id set the idValid property to true or
false and then call another method called "updateLoginButton" that says
something like 

if (idValid == true && passwordValid == true) 
	loginButton.enabeled = true;
else 
	loginButton.enabled = false;

or....

when the idValid or passwordValid fields are changed I fire a new event like

dispatchEvent( {type:"idStateChanged"});

and have my LoginForm register as a listener to its own "system" event and
then have it update the login button after receiving a "idStateChanged"
event ?

It seems to me that this should all be handled inside the LoginForm and not
be published as a system event but I wanted to confirm this before moving
forward as I'm new to the ARP framework.

Grant