passing url param to backing bean method - jsf-2

I have the following code in my Facelet:
<ui:composition template="/templates/mastertemplate.xhtml">
<ui:define name="pageTitle">
<h:outputFormat value="#{msgs.productPageTitle}">
<f:param value="#{param.productName}"/>
</h:outputFormat>
</ui:define>
<ui:param name="categoryName" value="#{param.categoryName}"/>
<ui:define name="content">
<p>#{param.productName}</p>
<h:form>
<h:commandLink action="#{cartBean.addItemToCart(param.productName)}">
<f:ajax event="action" render=":cart :cartPrice" />
<h:graphicImage value="resources/img/addToCart.gif"/>
</h:commandLink>
</h:form>
</ui:define>
</ui:composition>
It prints the #{param.productName} as it should. The cartBean expects a String as argument for its addItemToCart method (I know this is terrible, but not my choice). I have set up a logger in my cartBean and it tells me that the parameter is not coming through, it is empty.
If I do the following:
<h:commandLink action="#{cartBean.addItemToCart('someProductName')}">
<f:ajax event="action" render=":cart :cartPrice" />
<h:graphicImage value="resources/img/addToCart.gif"/>
</h:commandLink>
I substitute the #{param.productName} for a string literal, it works fine. Why can't I pass the param value as argument? I get an EvaluationException which explains why my logger sees an empty string but I don't understand how I should do this then.

Not sure if it's possible that way but at the very least it seems to be bad practice. You'd insert the string to your backing back without any validation/conversion options.
I found a tutorial which explains what you should do to make it work here.

Related

Passing and using parameters between JSF includes

I've been trying to understand JSF templating and include attributes and passing parameters between components. In Mastering JavaServer Faces 2.2 by Anghel Leonard, I came across the following example of passing parameters, which I don't fully understand.
Given this bean:
#Named
#ViewScoped
public class TemplatesBean implements Serializable {
private String msgTopDefault="";
private String msgBottomDefault="";
private String msgCenterDefault="No center content ... press the below button!";
public void centerAction(){
this.msgCenterDefault="This is default content";
}
// Getters and setters
}
Parameters are passed to contentDefault.xhtml with:
<ui:insert name="content">
<ui:include src="/template/default/contentDefault.xhtml">
<ui:param name="templatesBeanName" value="#{templatesBean}"/>
<ui:param name="contentPropertyName" value="msgCenterDefault"/>
</ui:include>
</ui:insert>
Then, within contentDefault.xhtml the parameters are used as follows:
<ui:composition>
<h:outputText value="#{templatesBeanName[contentPropertyName]}"/>
<h:form>
<h:commandButton value="Center Button" action="#{templatesBeanName['centerAction']()}"/>
</h:form>
</ui:composition>
I've never used the square-bracket syntax before, but if a reference to templatesBean is being passed in, why not just use that to access the properties or invoke action methods? For example, the following code works for me too and seems simpler:
<h:form>
<h:commandButton value="Center Button" action="#{templatesBeanName.centerAction()}"/>
</h:form>
Recognising that the example in the book may be a contrived example to illustrate a point, are there use cases where the other syntax is appropriate?
I do not know or own the book, so I cannot investigate that way what they want to illustrate, but I can sort of deduce that by looking at the full example you posted, not just the part about the centerAction.
If you look at
<ui:insert name="content">
<ui:include src="/template/default/contentDefault.xhtml">
<ui:param name="templatesBeanName" value="#{templatesBean}"/>
<ui:param name="contentPropertyName" value="msgCenterDefault"/>
</ui:include>
</ui:insert>
you'll see that 2 params are passesd on, templatesBeanName and contentPropertyName
In
<ui:composition>
<h:outputText value="#{templatesBeanName[contentPropertyName]}"/>
<h:form>
<h:commandButton value="Center Button" action="#{templatesBeanName['centerAction']()}"/>
</h:form>
</ui:composition>
from which you just pointed to the line with action="#{templatesBeanName['centerAction']()}", a dynamic bean with a static value in suqare brackets made into a method by adding () as a postfix, you'll see another line of code above it
<h:outputText value="#{templatesBeanName[contentPropertyName]}"/>
What effectively is done here is to have a dynamic bean AND a dynamic property name being used.
So my conclusion is that with this example what they are trying to illustrate is that you are able to pass on a dynamic bean, and on that bean use either both static or dynamic methods and properties(static properties and dynamic methods not being in the example)

f:param is not working with h:graphicImage

I'm getting <f:param> i.e., menuItemIndex value as null during my ajax call. Is it because it is with in <h:graphicImage> ??? Can any one suggest please? Note: Parameter is getting passed if I use <h:commandLink> instead of <h:graphicImage>.
<c:forEach items="#{cc.attrs.value}" var="menuItem" varStatus="loopItem">
....
<ui:fragment rendered="#{menuItem.hasChildren}">
<h:graphicImage library="images" name="#{menuItem.symbol}">
<f:ajax render=":fatcaForm:myMenu:menuID" event="click" listener="#{menuBean.refreshMenu}" />
<f:param name="menuItemIndex" value="{loopItem.count}" />
</h:graphicImage>
</ui:fragment>
....
</c:forEach>
The <h:graphicImage> is not a command component and it does therefore not support <f:param> children at all. The <f:param> works only when nested in an UICommand component, such as <h:commandLink> as you found out yourself.
So, this should do:
<h:commandLink action="#{menuBean.refreshMenu}">
<h:graphicImage library="images" name="#{menuItem.symbol}" />
<f:ajax render=":fatcaForm:myMenu:menuID" />
<f:param name="menuItemIndex" value="#{loopItem.count}" />
</h:commandLink>
(note that I fixed the EL syntax error in the <f:param value> as well)
Unrelated to the concrete problem, how you used the <h:graphicImage library> is not entirely right. Please carefully read What is the JSF resource library for and how should it be used?

Primefaces lightBox closes at click on commandLink

It's just a simple Primefaces lightBox I want to use commandLinks in. Unfortunately it simply closes, when I click a commandLink. Is there a way to keep the lightBox open?
Here an example of what my code looks like:
<ui:composition xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:p="http://primefaces.org/ui" template="template.xhtml">
<ui:define name="content">
<p:lightBox>
<h:outputLink value="#">
<h:outputText value="open lightbox" />
</h:outputLink>
<f:facet name="inline">
<h:form>
<h:commandLink>
commandLink
</h:commandLink>
</h:form>
</f:facet>
</p:lightBox>
</ui:define>
</ui:composition>
Use an ajax (asynchronous) request instead of a synchronous request:
<h:commandLink ...>
<f:ajax ... />
</h:commandLink>
or as you're using PrimeFaces already, just use <p:commandLink> instead (it uses by default already ajax):
<p:commandLink ... />
With ajax, by default no fresh page replacement with the response is performed (which basically "resets" anything to defaults). You can in case of <f:ajax> tell by render attribute which parts of the component tree should be updated in the client side and in <p:commandLink> by the update attribute. E.g. if you want to render/update the parent form only, use #form. E.g.
<p:commandLink ... update="#form" />

preRenderView-Event triggered before an action (commandbutton)

I am in a little bit of trouble with my preRenderView-Event. My page also uses a commandbutton to submit data but unfortunately the preRenderView-Event is always called before the buttons action is invoked.
The preRenderView-Event is responsible for loading data from a service. Since the page is simple and doesnt have to store any data I dont need any Session or ViewScoped-Beans.
As far as I understood the event is called in the Render-Response-Phase and the action in the button should happen somewhat earlier.
<h:body>
<f:metadata>
<f:viewParam name="id" value="#{bean.id}" converter="converter.SetOfLongConverter"/>
<f:event type="preRenderView" listener="#{bean.initializeData}" />
</f:metadata>
<ui:composition template="/META-INF/templates/myTemplate.xhtml">
<ui:param name="title" value="#{bean.title}"/>
<ui:define name="content">
<h:outputText value="#{bean.description}" />
<h:form>
<h:panelGrid columns="2">
<h:outputLabel value="Model" for="model" />
<h:inputText id="model" value="#{bean.model}" />
<h:outputLabel value="Manufacturer" for="manufacturer" />
<h:inputText id="manufacturer"
value="#{bean.manufacturer}" />
<h:outputLabel value="Year" for="year" />
<h:inputText id="year" value="#{bean.year}" />
</h:panelGrid>
<h:commandButton value="Create" type="submit" action="#{bean.create}" rendered="#{bean.createMode}"/>
<h:commandButton value="Save" type="submit" action="#{bean.save}" rendered="#{!bean.createMode}" />
</h:form>
</ui:define>
</ui:composition>
</h:body>
I added some Console-Messages to verify when the method in the bean is called and when I have the preRenderView-event it never happens.
Any advice what I am doing wrong here?
The <f:metadata> has to go inside <ui:define> of an <ui:composition>.
See also <f:metadata> tag documentation (emphasis mine):
Declare the metadata facet for this view. This must be a child of the <f:view>. This tag must reside within the top level XHTML file for the given viewId, or in a template client, but not in a template. The implementation must insure that the direct child of the facet is a UIPanel, even if there is only one child of the facet. The implementation must set the id of the UIPanel to be the value of the UIViewRoot.METADATA_FACET_NAME symbolic constant.
The simple reason is because the metadata is supposed to be view-specific, not template-specific.
Update: it turns out that the action method is not invoked at all. You've there a rendered attribute on the command button which seems according the symptoms to be dependent on a request based variable instead of a view based variable. Putting the managed bean in the view scope should fix this problem. See also commandButton/commandLink/ajax action/listener method not invoked or input value not updated

f:ajax within ui:repeat, unknown id for the component [duplicate]

This question already has answers here:
How to find out client ID of component for ajax update/render? Cannot find component with expression "foo" referenced from "bar"
(6 answers)
Closed 7 years ago.
When I try to render a panelGroup by an ajax call, it gives unknown id.
<h:form id="form1" prependId=false>
<h:panelGroup id="panel1">
<h:dataTable/>
<ui:repeat value="#{bean.page}" var="page">
<h:commandLink value="#{page}">
<f:ajax execute="#form" render="panel1" listener="#{bean.page}" />
</h:commandLink>
</ui:repeat>
</h:panelGroup>
</h:form>
When I tried this code, it gives unknown id panel1. I tried with id ":panel1" too. I get the same error.
A relative client ID (i.e. not starting with :) is relative to the current parent NamingContainer component. The <ui:repeat> is also a NamingContainer. So the render="panel1" is looking for the component within the context of <ui:repeat>. This isn't going to work. An absolute client ID (i.e. starting with :) is looking for the component within the context of view root. But you've it inside a <h:form> -which is in turn another NamingContainer component-, so the render=":panel" is also not going to work.
The following should work, with prependId="false" removed so that you can refer it:
<h:form id="form1">
<h:panelGroup id="panel1">
<h:dataTable/>
<ui:repeat value="#{bean.page}" var="page">
<h:commandLink value="#{page}">
<f:ajax execute="#form" render=":form1:panel1" listener="#{bean.page}" />
</h:commandLink>
</ui:repeat>
</h:panelGroup>
</h:form>
By the way, if you actually want to render only the table, then you should be doing this:
<h:form id="form1">
<h:panelGroup>
<h:dataTable id="table1" />
<ui:repeat value="#{bean.page}" var="page">
<h:commandLink value="#{page}">
<f:ajax execute="#form" render=":form1:table1" listener="#{bean.page}" />
</h:commandLink>
</ui:repeat>
</h:panelGroup>
</h:form>
Update: as per the comments, it turns out that you have changed the JSF default NamingContainer separator character from : to _ by configuration. In that case, you need to use _ instead of : in the client ID selector.
<f:ajax execute="#form" render="_form1_panel1" listener="#{bean.page}" />
<ui:repeat value="#{interaction.interactionListBean}" var="interactionItr">
<h:commandLink value="#{interactionItr.interactionDate}" styleClass="#{interaction.createImage}" style="margin:0 5px 5px 0!important; display:inline-block;"><br/>
<f:ajax render=":formId:interactionDate :formId:category :formId:activity :formId:status :formId:channel :formId:status1 :formId:caseId :formId:comment :formId:user1 :formId:team :formId:user :formId:transit "
listener="#{interactionController.interactionDetailGet}"/>
<f:param name="RefId" value="#{interaction.interactionRefId}"/>
</h:commandLink>
</ui:repeat>
problem :
please refer above with above code their is no exception on console but the ajax listerner will not invoke when I saw this post similiar kind of concept being use just I was place the exceute="#form" then my coding is working fine
solution:
execute="#form"

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