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.
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.
I am using JSF2, and I need to be able to pass a parameter from one JSF page to another via a commandLink.
I am on page funding.xhtml (ViewScoped) and have the following link defined:
<p:commandLink styleClass="toolbar"
action="/application/customerApplicationManagement.jsf">
<p:graphicImage url="/resources/gfx/search.png" />
<h:outputText value="#{msg.menu_searchApplications}" styleClass="toolbarLink" />
</p:commandLink>
I need to pass a string value to the customerApplicationManagement page indicating which page I came from so that after selecting an application, I can return to that page. I have tried several suggestions about how to pass this value including f:param, f:viewParam. I have even tried just adding it directly to the url (?fromPage=funding) etc, but they all seem to work only when the value is passed back to the current page, not a new page I am navigating to.
Can someone show me how this can best be accomplished.
Use <f:param> and <f:viewParam>:
Source page:
<p:commandLink styleClass="toolbar"
action="/application/customerApplicationManagement.jsf">
<p:graphicImage url="/resources/gfx/search.png" />
<h:outputText value="#{msg.menu_searchApplications}" styleClass="toolbarLink" />
<f:param name="fromPage" value="funding.xhtml" />
</p:commandLink>
Destination page (bound):
<f:metadata>
<f:viewParam name="fromPage" value="#{destinationBacking.fromPage}" />
</f:metadata />
<h:link value="Go back!" outcome="#{destinationBacking.fromPage}" />
Destination page (unbound):
<f:metadata>
<f:viewParam name="fromPage" />
</f:metadata />
<h:link value="Go back!" outcome="fromPage" />
Backing bean (only if you want to bind the param):
#ManagedBean
#ViewScoped
public class DestinationBacking{
String fromPage;
public String getFromPage(){
return fromPage;
}
public void setFromPage(String frompage){
fromPage = frompage;
}
}
Your view path will be binded to fromPage property from the destination backing bean and after you can use it to return to the original page.
Also I want to say that this way is a bit 'hackeable' by the end user, I mean, you're passing the original path through pure url. See also other ways to achieve that, as flash scope, which is very useful specially if you're working with #ViewScoped beans.
I don't know the specifics of the methods you tried to achieve your goal and hence we cant tell what was wrong with them, but if we consider your code 'as is' you don't have anything that will pass the string you want.
Not to repeat ourselves, there are plenty of answers here dedicated to using this or that method, so I will give you the best references, in my opinion, of course.
How can I pass a parameter to a commandlink inside a datatable;
ViewParam vs #ManagedProperty;
What can <f:metadata> and <f:viewParam> be used for.
Regarding the usage of back buttons in JSF you could also take a look at my own answer on How to get back to the same page in JSF.
By the way, using POST for page-to-page navigation is considered to be a bad practice. If all you need is to navigate to another page you'd better use plain <h:link> or <h:button> instead.
I have the same problem as user1598186 has stated in his question here : p:commandButton doesn't call bean's method in an <ui:include> page
However, no solution has been given (he has removed <ui:include> tags altogether and used variables instead)
Are there any ways of using <ui:include> and still have my backing bean's method executed, when I'm calling it inside the commandButton.
Any help will be much appreciated.
EL 2.2 method parameters (so, #{bean.method()} instead of #{bean.method}) can be used to pass a method signature that can be used in the actionListener attribute of a commandButton. The following is an example of passing a ManagedBean property as well as passing a method signature:
Main Page
<ui:include src="/jointeam.xhtml">
<ui:param name="propertyValue" value="#{managedBean.property1} />
<ui:param name="method" value="#{managedBean.performAction()}" />
</ui:include>
jointeam.xhtml
...
<h:inputText value="#{propertyValue}" />
...
<p:commandButton value="Submit" actionListener="#{method}" />
You can see how powerful this is in terms of code reuse and for many instances is less verbose and easier to use than composite components.
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>.
first, please forgive my ignorance and inability so use the search engine (i swear i have searched long and often but did not find any satisfying answer to this problem).
I have a bean implementing a action-listener compatible method:
#ManagedBean(name = "myBean")
#ViewScoped
class Bean{
public String myAction(ActionEvent event){
... = event.getComponent().getAttributes().get("something");
}
}
Then, i have a jsf component like this:
<composite:interface>
<composite:attribute name="actionBean" required="true"/>
<composite:attribute name="actionMethod" method-signature="void myAction(javax.faces.event.ActionEvent)" />
</composite:interface>
<composite:implementation>
<h:form>
<p:commandButton actionListener="#{cc.attrs.actionBean[cc.attrs.actionMethod]}">
<f:attribute name="something" value="somevalue" />
</p:commandButton>
</h:form>
</composite:implementation>
It is called something like this:
<namespace:myComponent actionBean="#{myBean}" actionMethod="myAction" />
I know that this call is not working, and i wonder how to do it right!
My main intention is that i want to have a relatively generic jsf-component (would be nice to have it reusable later), that contains a button. On click to this button i want to pass an object (no simple string! in case of string i would just use action="..." and pass it via f:param). With the actionListener method i take the object via event.getComponent().getAttributes().get("something").
I think the signature void myAction(javax.faces.event.ActionEvent) is the problem that breaks passing the related method to the component, isnt it? Is it in general possible to pass method with any argument to jsf components (and if yes, how)?
So, i hope there is a possible solution to solve the general problem with altering the above strategy or maybe use something nice and different (in general i prefer not to use any hacks or workarounds, but like to use what is intended by the framework).
Thanks if somebody would find the time to point me the way! In case this question already exists, would be nice to get to the related post and have this deleted.
Try following:
<namespace:myComponent myAction="#{myBean.myAction}"/>
And composite component:
<composite:interface>
<composite:attribute name="myAction"
required="true"
method-signature="void myAction(javax.faces.event.ActionEvent)"
targetAttributeName="actionListener"/>
</composite:interface>
<composite:implementation>
<h:form>
<p:commandButton id="myAction">
<f:attribute name="something" value="somevalue" />
</p:commandButton>
</h:form>
</composite:implementation>
Check composite:attribute documentation. It has several options to pass listeners to composite component. I used targetAttributeName for this.