form controls with the same property name

[schmod54]

How do I add error messages to a particular control if multiple controls share the same property name on the same page? E.g., say I have a user registration form, where usernames are unique. If a user enters a duplicate username, in my action bean I can add an error like so:

facesMessages.addToControlFromResourceBundle("username", "usernameExists");

But say I have a batch user registration process that allows someone to register 10 users at a time. If I use the same code, then the error message gets displayed at the top of the page and the user doesn't know which username is invalid. I could change the error message to contain the invalid name, but I would rather display it next to the relevant control. So how do I do that? Thanks!

[wise_guybg]

Normally you wouldn't have components with the same name. Why don't you add an index next to the name. Ex.: username1, username2...

Either way if you want them referenced from/to a backing bean you should have different fields!?

[schmod54]

My initial attempt was to do as you said... but it didn't work. I've played around with it and discovered that displaying faces messages attached to a control inside of a loop is problematic. Has anyone done this? The following is my code to allow users to modify a set of "Category" objects:

<a4j:repeat value="#{batchCategories}" var="cat">
 <ui:param name="i" value="#{batchCategories.rowIndex}"/>
 <s:decorate id="name#{i}Decorate" template="/inc/Field.xhtml">
 <ui:define name="label">Name:</ui:define>
 <h:inputText id="name#{i}" value="#{cat.name}"/>
 </s:decorate>
</a4j:repeat>

Instead of getting my form error messages displayed attached to the proper controls, I get:

WARNING: FacesMessage(s) have been enqueued, but may not have been displayed.

in my logs. My decorator is fine, and works if I hardwire it to a particular item, like so:

<ui:param name="cat" value="#{batchCategories.rowData}"/>
<ui:param name="i" value="#{batchCategories.rowIndex}"/>
<s:decorate id="name#{i}Decorate" template="/inc/Field.xhtml">
 <ui:define name="label">Name:</ui:define>
 <h:inputText id="name#{i}" value="#{cat.name}"/>
</s:decorate>

<ui:repeat> has the same behavior, except no warning in the logs. <c:forEach> doesn't display properly either... it puts all the messages in the global area. So... does anyone know how to display faces messages next to particular form controls inside a loop?

[wise_guybg]

I'm wondering about that

batchCategories.rowIndex

How have you realized it?

I also did not see how you have called

facesMessages.addToControlFromResourceBundle("username", "usernameExists");

You should be using indexes there too, right?

[schmod54]

I was a bit ambiguous in my previous posts, because I was mixing examples... also I was wrong about the exact problems I've had with different approaches. So I've made a simplified example that shows what I want to do, and how the different approaches fail. I'm running this in a seam-genned project on seam 2 beta, jboss 4.2.1.GA, but I expect it to behave the same way in other versions. Here is the source:

I have the following in my pages.xml... It's not strictly necessary to run the example though:

<page view-id="/control_loop_test.xhtml">
 <begin-conversation join="true"/>
 </page>

Here is an action bean that assigns facesMessages to form controls inside a loop:

import org.jboss.seam.ScopeType;
import org.jboss.seam.annotations.In;
import org.jboss.seam.annotations.Name;
import org.jboss.seam.annotations.Scope;
import org.jboss.seam.annotations.datamodel.DataModel;
import org.jboss.seam.faces.FacesMessages;

import java.util.Arrays;
import java.util.Collection;

@Name("controlLoop")
@Scope(ScopeType.CONVERSATION)
public class ControlLoopAction {

 @In
 private FacesMessages facesMessages;

 public static class MyEntity {
 private String name;

 public String getName() {
 return name;
 }

 public void setName(String name) {
 this.name = name;
 }
 }

 @DataModel
 private Collection<MyEntity> batchEntities = Arrays.asList(new MyEntity(), new MyEntity());

 public Collection<MyEntity> getBatchEntities() {
 return batchEntities;
 }

 public String submit(String controlPrefix) {
 for (int i = 0; i < batchEntities.size(); i++)
 facesMessages.addToControlFromResourceBundle(controlPrefix + "Name" + i, "badName" + i);
 return "/control_loop_test.xhtml";
 }
}

Here is a page that tries a few different ways of inputting data into the action bean.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html
 PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
 "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"
 xmlns:a4j="https://ajax4jsf.dev.java.net/ajax"
 xmlns:c="http://java.sun.com/jsp/jstl/core"
 xmlns:h="http://java.sun.com/jsf/html"
 xmlns:s="http://jboss.com/products/seam/taglib"
 xmlns:ui="http://java.sun.com/jsf/facelets">
<head>
 <title>Control Loop Test</title>
</head>
<body>
controlLoop: #{controlLoop}<br/>
global messages: <h:messages globalOnly="true"/><br/>
hardwired form... this works (at least for h:message anyway) but I really don't want to have to do this for large variable-size forms:
<h:form id="hardwiredForm">
 Name0:
 <h:inputText id="hardwiredName0" value="#{controlLoop.batchEntities[0].name}"/>
 s:message: <s:message/> h:message: <h:message for="hardwiredName0"/><br/>
 Name1:
 <h:inputText id="hardwiredName1" value="#{controlLoop.batchEntities[1].name}"/>
 s:message: <s:message/> h:message: <h:message for="hardwiredName1"/><br/>
 <h:commandButton value="Submit" action="#{controlLoop.submit('hardwired')}"/>
</h:form>
<br/>
a4j:repeat form... I'm thinking this doesn't work because the id of h:inputText gets resolved when the view is built... see
<a href="http://www.ninthavenue.com.au/blog/c:foreach-vs-ui:repeat-in-facelets">
 http://www.ninthavenue.com.au/blog/c:foreach-vs-ui:repeat-in-facelets</a>:<br/>
<h:form id="a4jRepeatForm">
 <a4j:repeat id="mainLoop" value="#{controlLoop.batchEntities}" var="myEntity" rowKeyVar="i">
 Name#{i}:
 <h:inputText id="a4jName#{i}" value="#{myEntity.name}"/>
 s:message: <s:message/> h:message: <h:message for="a4jName#{i}"/><br/>
 </a4j:repeat>
 <h:commandButton value="Submit" action="#{controlLoop.submit('a4j')}"/>
</h:form>
<br/>
ui:repeat form... same problem as a4j:repeat, but I don't want to use ui:repeat anyway because of its known bugs:
<h:form id="uiRepeatForm">
 <ui:repeat value="#{batchEntities}" var="myEntity">
 Name#{batchEntities.rowIndex}:
 <h:inputText id="uiName#{batchEntities.rowIndex}" value="#{myEntity.name}"/>
 s:message: <s:message/> h:message: <h:message for="uiName#{batchEntities.rowIndex}"/><br/>
 </ui:repeat>
 <h:commandButton value="Submit" action="#{controlLoop.submit('ui')}"/>
</h:form>
<br/>
c:forEach form... maybe this would work if I could get c: tags working... I tried some things I found on the web to get c: tags working, but none of them worked for me:<br/>
<h:form id="cForEachForm">
 <c:forEach id="mainLoop" value="#{controlLoop.batchEntities}" var="myEntity" varStatus="i">
 Name#{i.index}:
 <h:inputText id="forEachName#{i.index}" value="#{myEntity.name}"/>
 s:message: <s:message/> h:message: <h:message for="forEachName#{i.index}"/><br/>
 </c:forEach>
 <h:commandButton value="Submit" action="#{controlLoop.submit('forEach')}"/>
</h:form>

</body>
</html>

If anyone could show me how to get the facesMessages to correctly appear next to the relevant controls within the context of a loop, I'd greatly appreciate it. Thanks.

[pmuir]

http://jira.jboss.com/jira/browse/JBSEAM-1855

[schmod54]

Thanks. I voted for it.