How to send the currently iterated item to h:selectBooleanCheckbox with f:ajax event=change

Caau Dung Ngok picture Caau Dung Ngok · Jan 14, 2013 · Viewed 7.8k times · Source

I've the below form:

<h:form>
    <h:dataTable value="#{bean.items}" var="item">
        <h:column>
            <h:selectBooleanCheckbox  value="#{item.enabled}" valueChangeListener="#{bean.onchangeEnabled}">
                <f:ajax event="change" />
            </h:selectBooleanCheckbox>
        </h:column>
        <h:column>#{item.name}</h:column>
    </h:dataTable>
</h:form>

I would like to get #{item} or at least #{item.name} in the value change listener method:

public void onchangeEnabled(ValueChangeEvent e) {
    // I would like to get #{item.name} here too.
}

How can I achieve this?

Answer

BalusC picture BalusC · Jan 14, 2013

First of all, the valueChangeListener is the wrong tool for the job. Use <f:ajax listener>. Second, event="change" is the wrong choice in case of checkboxes/radiobuttons because their physical value actually never changes. You should use event="click", but this is the default already, so you can just omit it.

All in all, the proper initial code should look like this:

<h:selectBooleanCheckbox value="#{item.enabled}">
    <f:ajax listener="#{bean.onchangeEnabled}" />
</h:selectBooleanCheckbox>

with

public void onchangeEnabled(AjaxBehaviorEvent event) { // Note: event argument is optional.
    // ...
}

Once fixed it like that, then you can easily make use of EL 2.2 capability to pass method arguments:

<h:selectBooleanCheckbox value="#{item.enabled}">
    <f:ajax listener="#{bean.onchangeEnabled(item)}" />
</h:selectBooleanCheckbox>

with

public void onchangeEnabled(Item item) {
    // ...
}

See also: