4.1 and "do it once" components

[Geoff Callender]

I've got this working in 4.0 but need some help getting it working  
with 4.1.  It involves Tapestry's javascript.

I have some "do it once" components, eg. SubmitOnce and  
DirectLinkOnce; which address the problem of multiple clicks (causing  
duplicate submissions).  I've adapted them from the tapestry-bayeaux  
project and upgraded them to Tap 4.0.

In javascript they check if a variable called "ongoingSubmit" is  
true.  If not, they set it to true and do what Submit or DirectLink  
would normally do.  Otherwise they do nothing, ie. they ignore  
multiple clicks.  That much works just fine in both 4.0 and 4.1.

The tricky bit is when client validation detects an error and  
therefore ongoingSubmit should be set to false.  In 4.0 I handle this  
by overriding Tapestry javascript in my own script:

    Tapestry.default_invalid_field_handler = function(event, field,  
message)
        {
          if (!event.abort && !field.disabled)
          {
            Tapestry.set_focus(field);
            window.alert(message);
        
            event.abort = true;
            event.cancel_handlers = true;
        
            ongoingSubmit = false;
          }
        }

The only difference is one added line

            ongoingSubmit = false;

Q: In Tap 4.1, what should I do?  And is there a more elegant way  
than copying and pasting the entire function as I've done?

Geoff