Want to show a data table populated with data after a button click

Question

I want to write a code in this way, that If I click on a button a data table appears populated with data. before that there should not be the data table in view.

Answer 1

You can initialize a simple getter/setter :

private boolean visible = false; // getter/setter

public void getUserList(ActionEvent event)
{
    setVisible(true);

    // Your code
}

And modify your view like this :

<p:commandButton value="Go" styleClass="apply_button" actionListener="#{searchBean.getUserList}" update="table-wrapper">
    <f:attribute name="trigram" value="#{searchBean.trigram}"/>
    <f:attribute name="firstName" value="#{searchBean.firstName}"/>
    <f:attribute name="lastName" value="#{searchBean.lastName}"/>
</p:commandButton>

<h:panelGroup id="table-wrapper">
    <p:dataTable rendered="#{searchBean.visible}" value="#{searchBean.listUser}" var="user">
        <p:column headerText="Trigram">
            <h:outputText value="#{searchBean.trigram}"/>
        </p:column>
    </p:dataTable>
</h:panelGroup>

Note the update attribute on button, h:panelGroup wrapper and rendered attribute on table.