Question

I’m having difficulty finding support on this topic, because I know how to pass parameters to a template. What I want to do is pass parameters to not be used as parameters to the template but to a component within the template.

For example, in primefaces, you can write the following logic to create a button:

<p:commandButton action="#{printBean.print}">
  <f:attribute name="report" value="report.jrxml" />
</p:commandButton>

This is all fine and good when I don’t need to pass parameters. However, I need to construct a template which allows me to specify parameters to pass to the report dynamically. My first attempt was to do the following:

<p:commandButton actionListener="#{printBean.print}">
  <f:attribute name="report" value="report.jrxml" />
  <ui:insert name="reportParams" />
</p:commandButton>

Which would allow me to use the template in the following manner:

<ui:decorate template="templates/report.xhtml" >
  <ui:define name="reportParams>
    <f:attribute name="reportParam1" value="paramVal1" />
    <f:attribute name="reportParam2" value="paramVal2" />
    <f:attribute name="reportParam3" value="paramVal3" />        
    ...
  </ui:define>
</ui:decorate>

However parameters passed in this way are not received in my action listener in printBean, yet parameter “report” is. I think the attributes passed in this way are interpreted to mean that it is referring to the ui:define tag, and not to be inserted in the template as I would want.

Is there an alternative way of achieving the same way? Keep in mind I’m using JSF 2.0 and primefaces, but not Seam or any added libraries and ideally I would not have to add any libraries to make it work.

I apologize if an answer to this question already exists, but it’s maddening searching for an answer to this question.

EDIT: The number of parameters is variable, meaning I can’t simply use ui:param and put the value of that parameter as an attribute value within the template, because there could be many such parameters.

Answer 1

Use a composite component instead of a template.

Create this file /resources/mycomponents/printReport.xhtml:

<ui:component
    xmlns="http://www.w3.org/1999/xhtml"
    xmlns:ui="http://java.sun.com/jsf/facelets"
    xmlns:cc="http://java.sun.com/jsf/composite"
    xmlns:p="http://primefaces.org/ui"
>
    <cc:interface>
        <!-- No attributes. -->
    </cc:interface>
    <cc:implementation>
        ...
        <p:commandButton value="Print" action="#{printBean.print}" />
        ...
    </cc:implementation>
</ui:component>

Use it as follows:

xmlns:my="http://java.sun.com/jsf/composite/mycomponents"
...
<my:printReport>
    <f:attribute name="reportParam1" value="paramVal1" />
    <f:attribute name="reportParam2" value="paramVal2" />
    <f:attribute name="reportParam3" value="paramVal3" />
</my:printReport>

Rewrite the print method as follows:

public void print() {
    UIComponent composite = UIComponent.getCurrentCompositeComponent(FacesContext.getCurrentInstance());
    String reportParam1 = (String) composite.getAttributes().get("reportParam1");
    String reportParam2 = (String) composite.getAttributes().get("reportParam2");
    String reportParam3 = (String) composite.getAttributes().get("reportParam3");
    // ...
}