JSF and richfaces: h:commandlink in richfaces table not working properly - jsf

When using h:commandlink(or commandbutton) inside a rich:dataTable, the action specified is never invoked, neither is the corresponding managed bean instantiated(whether it is at request or session scope)...
instead, the same request is performed.. (page reloads)..
have seen what appeared to be similar issue on forums, but is not actually the problem i am having..
the h:commandlink /button work ok outside of the rich:datatable..
Does anyone have any advice?
here is a code snippet:
<h:commandLink id="commLink" actionListener="#{hBean.test}" action="#{hBean.viewTranslation}">
<h:outputText value="#{trans.translationName}"/>
</h:commandLink>
</rich:column>

The bean is apparently request scoped and the datamodel is not been loaded during bean's construction (at least, during apply request values phase of the subsequent request). You need to preserve the same datamodel for the subsequent request, else JSF cannot locate the row item associated with the clicked link. The most straightforward way is to load the datamodel in the bean's constructor or #PostConstruct method.
A quick fix/test is to put bean in session scope. The datamodel will then be saved in the session scope and be available in the subsequent request. But this has more impact on user experience (e.g. unexpected results when having the same page opened in different browser windows/tabs in the same session). If you're already on JSF 2.0 (which is likely not the case since you're using RichFaces), then the new view scope would have been the solution.
Related questions:
h:commandLink is not been invoked - contains an overview of all possible causes of this behaviour.

If you are using RichFaces 3.0.0 through 3.3.3, use the tag a4j:keepAlive. It will works even with request scope.

Related

How to restore ViewScoped bean when user clicks back button?

Lets say I have a #ViewScoped Bean behind my current page A. Now the user navigates to page B via a normal get request, lets say to www.google.com.
When the user clicks the back button of the browser, I would like to restore the #ViewScope of the previous page, so that it appears exactly as it was left. Is that possible to achieve somehow?
I dont want to make my page A #SessionScoped so that the backing beans do not disturb each others state when opened in two browser tabs.
Since version 2.6 OmniFaces has this feature, is called #ViewScoped(saveInViewState = true) But with some caution!
It's very important that you understand that this setting has potentially a major impact in the size of the JSF view state, certainly when the view scoped bean instance holds "too much" data, such as a collection of entities for a data table, and that such beans will in fact never expire as they are stored entirely in the javax.faces.ViewState hidden input field in the HTML page. Moreover, the #PreDestroy annotated method on such bean will explicitly never be invoked, even not on an unload as it's quite possible to save or cache the page source and re-execute it at a (much) later moment.
A more programmatical solution is the #ConversationScoped. With the convertsation id as parameter can you restore the view.
conversationscope example
Yes it is possible, pass parameter like this using f:param this will pass your parameter to the next screen.
<h:commandLink action="screenName" value="#{search.participantName}">
<f:param value="#{searchcus.participantId}" name="PARTICIPANT_ID"/>
<f:param name="PARENT_SCREEN_CODE" value="SEARCH_PARTICIPANT"/>
</h:commandLink>
After that in init() method get value as a parameter to fetch the result.

Rendering Condition in JSF 1.2 [duplicate]

I know this type of question has been asked million times here, but I couldn't find a solution for my problem in relevant posts.
JSF 1.2
I have a request-scoped bean with a method used as valueChangeListener:
class DoStuff{
...
public void step1ChkStuffIncluded_CheckedChanged(ValueChangeEvent event){
StuffDocument cd = (StuffDocument)getInfo("StuffDocument");
if(cd == null){
Logger.Error("DoStuff", "step1ChkStuffIncluded_CheckedChanged", "No stuff document (null)");
return;
}
if (step1ChkStuffIncludedChecked){
cd.handleChecked();
}
else{
cd.handleUnchecked();
}
}
...
}
by a selectBooleanCheckbox component as follows (.jspx):
...
</h:panelGroup>
<h:panelGroup rendered="#{DoStuff.pnlStep1}">
<p>
<label for="step1ChkStuffIncluded">#{DoStuff.step1ChkStuffIncludedText}</label>
<h:selectBooleanCheckbox
id="step1ChkStuffIncluded"
onchange="submit();"
value="#{DoStuff.step1ChkStuffIncludedChecked}"
valueChangeListener="#{DoStuff.step1ChkStuffIncluded_CheckedChanged}">
</h:selectBooleanCheckbox></p>
</h:panelGroup>
<div id="someDiv">
...
where
xmlns:h="http://java.sun.com/jsf/html"
Whenever the bean's scope is session, both setter and the listener for the checkbox are executed, but not in request scope. Unfortunately I can't find any clues other than that.
Any advise is greatly appreciated. Requests for further clarifications are welcome.
You've there a rendered="#{DoStuff.pnlStep1}" on a parent component. During processing of the form submit, JSF will as part of attack safeguard determine if the input component (and all of its parents) is rendered according to the server side conditions. If it's not rendered, then it will simply be skipped altogether during the processing.
That it works in a session scoped bean but fails in a request scoped bean indicates that the value behind rendered="#{DoStuff.pnlStep1}" is determined based on some request based variable/condition which was present during the request of displaying the form, but is absent during the request of processing the form submit.
To fix this, you need to make sure that you preserve exactly the same variable/condition for the value behind rendered="#{DoStuff.pnlStep1}" during the request of processing the form submit. There are several ways to achieve this, depending on the nature of the condition and how you're submitting the form. One of the ways is to pass the request based variable/condition back as a request parameter by <f:param> or <h:inputHidden>.
The canonical JSF 2.0 fix would be to put the bean in the view scope which is not available in JSF 1.2, but can be simulated using Tomahawk's <t:saveState> component.
See also:
JSF 1.2: How to keep request scoped managed bean alive across postbacks on same view?
How to call an action method of a UICommand Component which was rendered conditionally?

Should JSF process non rendered components on Ajax re-rendering?

My page has Ajax show/hide functionality.
During the initial page load my bean methods that are inside a non rendered <f:subview> or <h:panelGroup> are not called. When re-render the #form using Ajax, my bean methods are getting called although the relevant subviews are not rendered. Is this what should happen? (I am using JSF 2.2)
This is the expected behaviour as per my comment above. Unfortunately it comes with some ugly behaviour.
If you an object that is doing anything when using the list, it will work fine on your first request. Even if you have taken your precautions say by loading something with f:event this will not save you on the following AJAX request.
Example:
If you use JPA with each bean managed for the scope of the request and that bean has a lazy collection that is not rendered this will cause the following:
Request 1: Non-rendered components will not be touched i.e. Lazy collections will not initialize
Request 2(Ajax): JSF will try to restore the full view calling your non-loaded lazy collection resulting to an exception.

JSF Required=Yes not working inside a datatable?

I searched everywhere but could not find a solution to this. I am trying to used
required=yes to validate whether a value is present or not. I am using it inside inputtext.
The problem is it does not work inside a datatable. If I put the text box outside the datatable it works. I am using JSF 1.7 so I don't have the validateRequired tag from JSF 2.0.
I even used a validator class but it is still not working. Does anyone know why does required=yes or validator='validationClass' inside a inputtext inside a datatable is not working.
I appreciate the help.
Thanks.
First of all, the proper attribute values of the required attribute are the boolean values true or false, not a string value of Yes. It's an attribute which accepts a boolean expression.
The following are proper usage examples:
<h:inputText required="true" />
<h:inputText required="#{bean.booleanValue}" />
<h:inputText required="#{bean.stringValue == 'Yes'}" />
As to the problem that it doesn't work inside a <h:dataTable>, that can happen when the datamodel is not been preserved properly (the datamodel is whatever the table retrieves in its value attribute). That can in turn happen when the managed bean is request scoped and doesn't prepare the datamodel during its (post)construction which causes that the datamodel is null or empty while JSF is about to gather, convert and validate the submitted values.
You need to ensure that the datamodel is exactly the same during the apply request values phase of the form submit request as it was during the render response phase of the initial request to display the form with the table. An easy quick test is to put the bean in the session scope. If that fixes the problem, then you definitely need to rewrite the datamodel preserving logic. You could also use Tomahawk's <t:saveState> or <t:dataTable preserveDataModel="true"> to store the datamodel in the view scope (like as JSF2's new view scope is doing).
Finally, JSF 1.7 doesn't exist. Perhaps you mean JSF 1.2?

JSF 2 : Accessing managed bean's instance in the phase listener object?

Is it possible to get a reference to the to-be-executed managedbean in the before-invokeApplication-phaselistener ?
Before the invoke application phase, it should be clear which managedBean that is going to execute the method.
For the sake of the example, assume there's 1 main manage bean to handle 1 jsf page.
So what i need is basically :
The user access the program from the menu
Because it's accessed from the menu, the main manage bean's init() method gets called to initialize stuffs like preparing data, doing authorization checks
Subsequent submits dont need to call the init() method anymore until it's reaccessed from the menu
To implement the point #2, im thinking of intercepting one of the phases
I've checked the API docs about getting the managed bean in the phases implementation, but i couldnt seem to find any.
After typing this question, i realize i could do this in #PostConstruct or the managed bean's constructor, but that would do only at the first time the bean is constructed, and my need is to call the method everytime the jsf is being accessed from the menu.
Any suggestions ?
Regards,
Albert Kam
You can access your managed beans via the ELContext/ELResolver. This is explained nicely in the MyFaces wiki (also works in vanilla JSF).
For example:
ELContext elContext = FacesContext.getCurrentInstance().getELContext();
NeededBean neededBean = (NeededBean) FacesContext.getCurrentInstance().getApplication()
.getELResolver().getValue(elContext, null, "neededBean");
See the MyFaces wiki entry for further explanation, and implementations for other JSF versions.
Your idea of using #PostConstruct is a good one. Consider changing your scope to something liked #ViewScoped, so the logic is executed everytime you navigate to that view.
Also, have a look at the PreRenderViewEvent (for JSF 2). This code is embedded in your facelet page:
<f:metadata>
<f:viewParam name="foo" value="#{bean.foo}"/>
<f:event type="preRenderView" listener="#{bean.doSomething}"/>
</f:metadata>
The f:event listener is executed before every page view.

Resources