Re: Setting focus on input fields

From: Jason Lee <>
Date: Tue, 8 Apr 2008 08:28:11 -0500

On Mon, Apr 7, 2008 at 6:02 PM, Jim Driscoll <> wrote:

> The problem with this, is that you don't get to write out the javascript
> after the inputText is rendered - only before. But you need the id to exist
> before you can set a focus on it. So I'm stumped as to how to do simple
> seeming example. I imagine you'd have to do all kinds of painful things
> with Phaselisteners and stream parsing. Ouch.
> If you could, in a simple fashion, queue the javascript for the end of the
> page when you hit a tag, that would solve things... but that's 2.0 stuff,
> right? Or is that going to even be possible in 2.0?

Yeah, I think that approach might have to be a 2.0 thing, unless you want to
buffer and parse the output, which I don't. :) You could probably do this
pretty easily, though:


That would be pretty simple.

> Hmm. I've been thinking about this - don't most id crossreferences only
> use same-form id's? It would probably be less confusing to the enduser to
> embed it into a form and do a <foo:focus for="componentID" /> rather than
> have it be outside the form and do a <foo:focus for="formID:componentID" />
> Implementation of this version is trivial - I had it done in about an hour
> (which is why I started it as my first component effort).

I've seen it go both ways. My slider component in Mojarra Scales, for
example, has a for attribute. The slider itself is a ValueHolder, but,
using for="foo:bar", one can update one or more other DOM elements.

> This should be doable with a fairly straightforward script in JavaScript,
> but it would seem less useful than the qualified version. Maybe as a default
> action for the focus tag without a "for" attribute? But that would also mean
> that you'd have to set tabindex for all the fields, which doesn't seem like
> common practice for simple forms (and for more complex forms, you're
> probably doing javascript anyway, and don't need this tag).

Maybe so. I was just thinking as I typed... :P

> If you don't mind, Jason, I'd like to have a crack at just doing a version
> for 1.2 with the <mj:focus for="componentID"/> format... Then we can tweak
> it. In particular, if you have an insight on how to emit javascript at the
> right time with a wrapping inputText tag, I'd love to know even if you don't
> think you have time - it's going to bother me until I figure out how.

That works for me (and, at the time I'm writing this, there's a change
bundle for review, so... ;)

> And of course, for all of this, we're talking about 1.2.
> For 2.0, I agree with Jacob that it makes most sense to have it be an
> attribute of f:view... i.e. <f:view focus="formID:clientID">

I agree. That would be nice.

Jason Lee, SCJP
Software Architect -- Objectstream, Inc.
Mojarra and Mojarra Scales Dev Team