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How can I show/hide component with JSF?

How can I show/hide component with JSF? I am currently trying so do the same with the help of javascript but not successfull. I cannot use any third party libraries.

Thanks| Abhi

like image 419
Abhishek Dhote Avatar asked Sep 12 '10 10:09

Abhishek Dhote


3 Answers

You can actually accomplish this without JavaScript, using only JSF's rendered attribute, by enclosing the elements to be shown/hidden in a component that can itself be re-rendered, such as a panelGroup, at least in JSF2. For example, the following JSF code shows or hides one or both of two dropdown lists depending on the value of a third. An AJAX event is used to update the display:

<h:selectOneMenu value="#{workflowProcEditBean.performedBy}">
    <f:selectItem itemValue="O" itemLabel="Originator" />
    <f:selectItem itemValue="R" itemLabel="Role" />
    <f:selectItem itemValue="E" itemLabel="Employee" />
    <f:ajax event="change" execute="@this" render="perfbyselection" />
</h:selectOneMenu>
<h:panelGroup id="perfbyselection">
    <h:selectOneMenu id="performedbyroleid" value="#{workflowProcEditBean.performedByRoleID}"
                     rendered="#{workflowProcEditBean.performedBy eq 'R'}">
        <f:selectItem itemLabel="- Choose One -" itemValue="" />
        <f:selectItems value="#{workflowProcEditBean.roles}" />
    </h:selectOneMenu>
    <h:selectOneMenu id="performedbyempid" value="#{workflowProcEditBean.performedByEmpID}"
                     rendered="#{workflowProcEditBean.performedBy eq 'E'}">
        <f:selectItem itemLabel="- Choose One -" itemValue="" />
        <f:selectItems value="#{workflowProcEditBean.employees}" />
    </h:selectOneMenu>
</h:panelGroup>
like image 136
Kevin Rahe Avatar answered Nov 13 '22 10:11

Kevin Rahe


Generally, you need to get a handle to the control via its clientId. This example uses a JSF2 Facelets view with a request-scope binding to get a handle to the other control:

<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
  "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
      xmlns:h="http://java.sun.com/jsf/html">
  <h:head><title>Show/Hide</title></h:head>
  <h:body>
    <h:form>
      <h:button value="toggle"
               onclick="toggle('#{requestScope.foo.clientId}'); return false;" />
      <h:inputText binding="#{requestScope.foo}" id="x" style="display: block" />
    </h:form>
    <script type="text/javascript">
      function toggle(id) {
        var element = document.getElementById(id);
        if(element.style.display == 'block') {
          element.style.display = 'none';
        } else {
          element.style.display = 'block'
        }
      }
    </script>
  </h:body>
</html>

Exactly how you do this will depend on the version of JSF you're working on. See this blog post for older JSF versions: JSF: working with component identifiers.

like image 17
McDowell Avatar answered Nov 13 '22 11:11

McDowell


Use the "rendered" attribute available on most if not all tags in the h-namespace.

<h:outputText value="Hi George" rendered="#{Person.name == 'George'}" />
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Thorbjørn Ravn Andersen Avatar answered Nov 13 '22 10:11

Thorbjørn Ravn Andersen