JSF messes up form component id

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swe_dev1 - 02 Dec 2005 14:55 GMT

Hello,

I am trying to get a JSF-form to call a javascript and passing a
component id as a variable, but somehow the variable remains undefined
when seen by the java script. I simply want to make a drop down menu
("county") to be automatically populated when a choice is made in
another drop down menu ("district") without reloading the page. My jsf
looks like this:

<html>
<head>
<%@ taglib uri="http://java.sun.com/jsf/html" prefix="h" %>
<%@ taglib uri="http://java.sun.com/jsf/core" prefix="f" %>
<script language="JavaScript" src="autopop.js"></script>
</head>
<body>
<f:view>
<h:form id="searchform1">
    <h:selectOneMenu id="district"
onchange="menuSelect(this,document.forms.searchform1.county);">
        <f:selectItem itemValue="aa" itemLabel="District 1"/>
        <f:selectItem itemValue="ab" itemLabel="District 2"/>
        <f:selectItem itemValue="ac" itemLabel="District 3"/>
        <f:selectItem itemValue="ad" itemLabel="District 4"/>
    </h:selectOneMenu>
    <h:selectOneMenu id="county" styleClass="infield"></h:selectOneMenu>
</h:form>
</f:view>
</body>
<html>

As you can see, two variables are passed, "this", which works fine, and
"document.forms.searchform1.county" which gets a null value. When I do
this without JSF it all works fine, but JSF renames the component id:s
(it adds the form name and semicolon). Therefore I can't seem to
reference it properly...

What am I doing wrong? Is there another, more "JSF-ish" way to do this?

Any help is greatly appreciated!

/Erik

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Andrea Desole - 02 Dec 2005 15:27 GMT

> Hello,
>
[quoted text clipped - 32 lines]
> (it adds the form name and semicolon). Therefore I can't seem to
> reference it properly...

that's correct. That's how JSF does it. It follows the entire component
hierarchy down to your component, adding, for each component on the
path, the component name and a semicolon

> What am I doing wrong? Is there another, more "JSF-ish" way to do this?

You can just change the id in your javascript call, using the convention
that JSF uses. What I'm not sure about is if the separator will always
be a semicolon.
A more JSF-ish way would probably be to make your own component, and
generate your script in the render phase. I'm not sure it's worth it

Reply to this Message

Chris Smith - 02 Dec 2005 16:00 GMT

> You can just change the id in your javascript call, using the convention
> that JSF uses. What I'm not sure about is if the separator will always
> be a semicolon.

In fact, it will NEVER be the semicolon. I'm very confused that you and
Erik both seem to see the semicolon used, but that's not in accordance
with the JSF specification. Section 3.2.3 requires that this delimiter
be a colon, not a semicolon. Perhaps there's a major third-party JSF
implementation that I haven't tried which doesn't comply. MyFaces,
perhaps?

So the spec says you ought to be safe... but obviously your use of a
non-compliant JSF implementation negates that guarantee.

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Reply to this Message

Andrea Desole - 02 Dec 2005 16:09 GMT

> In fact, it will NEVER be the semicolon. I'm very confused that you and
> Erik both seem to see the semicolon used, but that's not in accordance
> with the JSF specification. Section 3.2.3 requires that this delimiter
> be a colon, not a semicolon. Perhaps there's a major third-party JSF
> implementation that I haven't tried which doesn't comply. MyFaces,
> perhaps?

sorry, my bad English :-(.
Yes, I meant colon. I assume Erik made the same mistake

Reply to this Message

swe_dev1 - 05 Dec 2005 07:59 GMT

Chris & Andrea,

You are of course right, it is a colon and nothing else...

However, this still poses a problem since the reference

onchange="menuSelect(this,document.forms.searchform1:county);"

or any other reference with a colon gives an error, and a strange one
too: it says that ")" is missing. I simply assume that component
references can only be made with dot:s (.)

Any ideas?

/Erik

Andrea Desole skrev:

> > In fact, it will NEVER be the semicolon. I'm very confused that you and
> > Erik both seem to see the semicolon used, but that's not in accordance
[quoted text clipped - 5 lines]
> sorry, my bad English :-(.
> Yes, I meant colon. I assume Erik made the same mistake

Reply to this Message

Andrea Desole - 05 Dec 2005 09:11 GMT

> Chris & Andrea,
>
[quoted text clipped - 9 lines]
>
> Any ideas?

I'm not a javascript expert, but you are probably doing something wrong.
Colons must work, otherwise JSF wouldn't be able to write its own scripts.
Also, looking at your javascript, I think you are directly referencing
the component, without referencing the form. Try

document.forms.searchform1.searchform1:county

or try to use the syntax that JSF uses for the command link:

document.forms['searchform1']['searchform1:county']

Or, even better, ask the javascript newsgroup :-)

Reply to this Message

swe_dev1 - 05 Dec 2005 14:32 GMT

Andrea,

The follwong worked:

document.forms['searchform1'].elements['searchform1:county']

Thanks for your help!

/Erik

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JSF messes up form component id

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