Validation with PrimeFaces

Question

I have a form with one field called emai has a very simple validation required = true . now when I click on the button bellow it performs AJAX callback. I wonder anyway to make the validation done on the client side without calling the server?

<h:form class="lfrm" id="lfrm">
    <p:panel id="lpanel" header="Login">
        <p:messages id="lmessages" showDetail="true" autoUpdate="true"/>

        <h:panelGrid id="lgrid" columns="2" cellpadding="5">
            <h:outputText value="Email: *" />

            <p:inputText styleClass="email"
                         id="lemail"
                         value="#{Registration.user.email}"
                         required="true" requiredMessage="Email is required">
            </p:inputText>

            <p:commandButton process="lemail"
                             value="Sign in"
                             immediate="true"
                             validateClient="true"/>
    </p:panel>
</h:form>

Answer 1

Add the following configuration in web.xml

<context-param>
    <param-name>primefaces.CLIENT_SIDE_VALIDATION</param-name>
    <param-value>true</param-value>
</context-param>

Also if you set ajax to false, the current form where the component lives is sent. ie the form which contains the p:commandButton. If ajax used, choose what you want to process. use the following tag to process the fields to the command button

<p:commandButton process="@form" ...... />