I'm using dynamically created links:
<h:link outcome="/page" value="#{name}">
<f:param name="name" value="#{name}"/>
</h:link>
I would like to attach custom converter for f:param to remove spaces from #{name} etc.
But there is no converter property in f:param.
A Converter is intented to convert from submitted String request parameter values to complex objects and vice versa in input fields. However, the <f:param> is pure output only and it will always call toString() on the value. It doesn't support a Converter.
Your cleanest and best bet is to create a custom EL function, so that you ultimately end up like:
<f:param name="name" value="#{util:prettyUrl(name)}"/>
Update: the JSF utility library OmniFaces has since version 1.4 (March 2013) a <o:param> component which extends the <f:param> with support for a fullworthy JSF converter, exactly like as you'd use in <h:outputText converter>.
<h:link outcome="/page" value="#{name}">
<o:param name="name" value="#{name}" converter="somePrettyURLConverter" />
</h:link>
See also the showcase.
what if you do something like this?
<f:param name="name" value="#{name.replace(' ', '')}" />
Isn't this working?
Or you want for all < f:param ... ??
Regards
Related
I have use case in which I have to use resource bundle to display various texts on UI. Some of these resource bundle entries take paramets (e.g. {0}), for these I use h:outputFormat but sometimes that isn't enough.
e.g.
someMessage=Display this message with param {0}
in a resource bundle.
To display it on xhtml I normally do:
<h:outputFormat value="#{msg['someMessage']}"><f:param value="#{someBean.value}"/></h:outputFormat>
That works well when it's a simple case, but for more complex use cases it isn't enough. For example if I want the 'title' attribute of a commandLink to use the above resource bundle entry:
<h:commandLink action="logout" title="#{msg['someMessage']}">
<f:param value="#{someBean.value}" />
<h:graphicImage library="images" name="image.png" />
</h:commandLink>
which doesn't work. I also tried:
<h:commandLink action="logout">
<f:attribute name="title">
<h:outputFormat value="#{msg['someMessage']}"><f:param value="#{someBean.value}"/></h:outputFormat>
</f:attribute>
<h:graphicImage library="images" name="image.png" />
</h:commandLink>
which also doesn't work since f:attibute doesn't allow children.
Even if there is a hack to bypass this (e.g. using hover component from primefaces) there are other fields that might require a parameterized message.
Does anyone know of a way to use MessageFormat that takes an argument in a non-value field of a JSF component?
You could create a custom EL function for this with which you can ultimately end up like:
<h:commandLink ... title="#{my:format(msg['someMessage'], someBean.value)}" />
You can use the MessageFormat API to perform the job, exactly as <h:outputFormat> is doing under the covers.
An alternative is to create a custom component which does the same as JSTL's good 'ol <fmt:message> which supports a var attribute to export the formatted message into the EL scope.
<my:outputFormat ... var="linkTitle">
...
</my:outputFormat>
<h:commandLink ... title="#{linkTitle}" />
Update: JSF utility library OmniFaces has #{of:formatX()} functions and a <o:outputFormat> component for the very purpose.
The given problem is that passing complex parameter (see code example below) doesn't work in JSF.
<h:outputFormat value="Final result is: {0}">
<f:param>
<h:outputFormat value="{0} to {1}">
<f:param value="#{mngr.lowerBound}"/>
<f:param value="#{mngr.upperBound}"/>
</h:outputFormat>
</f:param>
</h:outputFormat>
I'm NOT looking for the solution that uses the ManagedBean, like this:
<h:outputFormat value="Final result is: {0}">
<f:param value="mngr.formattedParams />
</h:outputFormat>
However there is a proper solution that works in OmniFaces:
JSF-2. h:outputFormat. Complex f:param
I'm wondering if there is also a solution in PrimeFaces?
No PrimeFaces does not have this. There is no reason to either since OmniFaces has it. And they both target different aspects of JSF: ui component suite vs utility suite so fully complementary
I created a custom JSF tag:
<ui:composition>
<h:panelGroup>
<rich:dataScroller id="#{id}" for="#{table}" execute="#{table}"
page="#{scrollerPage}" render="#{table}-sc1" maxPages="5"
fastControls="hide" oncomplete="#{onCompl}" scrollListener="#{scrollListenerBean[scrollListenerMethod]}" />
<h:inputText value="#{scrollerPage}" id="#{table}-sc1" size="2">
<f:convertNumber integerOnly="true" />
</h:inputText>
<h:outputText styleClass="outputText"
value=" of #{scrollPagesCount} " />
<h:commandButton value="GO! " />
</h:panelGroup>
</ui:composition>
To pass the listener method, I used the solution suggested in a quite old blog:
<my:dataScroller id="idDS1" table="table1"
scrollerPage="#{bean.navigationHelper.scrollerPage}"
scrollPagesCount="#{bean.navigationHelper.scrollPagesCount}"
onCompl="initForm();"
scrollListenerBean="#{bean}"
scrollListenerMethod="aMethod" />
My questions are: is this the best way to do this? How can I make the method optional?
Thanks a lot for any Help! bye!
My questions are: is this the best way to do this?
That's the only way anyway, provided that you can only use standard JSF/EL facilities and you cannot create a custom taghandler.
You could however create a custom taghandler to convert the value expression to a method expression. The OmniFaces JSF utility library has a <o:methodParam> for exactly this purpose. See also the <o:methodParam> demo page.
You could then end up like:
<my:dataScroller ... scrollListener="#{bean.aMethod}" />
and
<o:methodParam name="scrollListenerMethod" value="#{scrollListener}" />
<rich:dataScroller ... scrollListener="#{scrollListenerMethod}" />
See also:
Dynamic ui include and commandButton
How can I make the method optional?
Theoretically, you could use JSTL tags to build the view conditionally. Something like:
<h:someComponent>
<c:if test="#{not empty fooAttribute}">
<f:attribute name="foo" value="#{fooAttriubte}" />
</c:if>
</h:someComponent>
But that's in the particular case of a special method expression listener attribute unfortunately not possible. There's no such thing as <rich:scrollListener> or something which allows you binding a RichFaces specific scrollListener as a separate tag to the <rich:dataScroller>. Best what you could do without creating custom taghandlers is duplicating the whole <rich:dataScroller> in two <c:if>s (or a <c:choose>); one with and other without scrollListener. This is too clumsy. You'd really better create a custom <my:richScrollListener> taghandler for this which you could then place in a <c:if>.
I've got the following h:commandButton:
<h:commandButton action="#{myBean.myAction}" value="Send">
<f:param name="myFlag" value="true" />
</h:commandButton>
I want to gain access to myFlag insinde a Validator, that's attached to another element with f:validator.
Unfortunately, when I want to retrieve the parameter through the FacesContext, I only get null returned.
Is it that the parameters are only sent once all validators have been invoked?
The <f:param> inside <h:commandButton> is only supported since JSF 2.0, but you're using JSF 1.2. The <f:param> is then only supported in <h:commandLink>.
<h:commandLink action="#{myBean.myAction}" value="Send">
<f:param name="myFlag" value="true" />
</h:commandLink>
There are alternatives, such as a <h:inputHidden> or <f:setPropertyActionListener> or <f:attribute> or in this case perhaps just plain <input type="hidden"> (the hidden input component and the action listener will only set their value during update model values which is later than validations phase; the attribute tag has better to be set on the component which invokes the validator). As the functional requirement is unclear, it's not possible to suggest the best alternative.
Update as per the comments, apparently all you need to know is if the particular button is pressed or not; in that case just give it and the parent form a fixed ID
<h:form id="form">
<h:commandButton id="send" ...>
this way it will have a fixed request parameter name of form:send and you could check on that in the validator:
if (externalContext.getRequestParameterMap().containsKey("form:send")) {
// Send button is pressed.
}
You can by the way also check for that in the required validators as follows:
<h:inputText ... required="#{not empty param['form:send']}" />
See also:
Action dependent requireness
Is there a way to call java method in .xhtml?
I just want to be able to call java.net.URLEncoder.encode() method from xhtml file.
Is it possible to do this?
In jsp it was very easy to do
Use <f:param>.
<h:outputLink value="page.jsf">
<f:param name="foo" value="#{bean.foo}" />
<f:param name="bar" value="#{bean.bar}" />
</h:outputLink>
This will end up in page.jsf?foo=encodedFooValue&bar=encodedBarValue.
Note: scriptlets indeed eases writing raw Java code in a view template, but that does still not make it a good practice! Use taglibs/EL whenever possible, else the particular logic simply belongs in a real Java class such as a backing bean constructor or method.