Accordion panel appears open, but doesn't show content

问题

I want to show the first tab, and by default (I mean, without activeIndex) it shows me that tab, but it doesn't show the content.

<p:accordionPanel id="acordeon" value="#{editarReporteExcelBean.reporteOperacionDtoList}" var="reporteOperacion" activeIndex="0" >
    <p:tab id="areaTab" >
        <f:facet name="title">Area #{reporteOperacion.area.nombre}</f:facet>
        <anglosgi:reporteOperacion id="reporteOperacion1"
                            reporteOperacionDto="#{reporteOperacion}"
                            formId="reporteForm"
                            contenedorId="reporteForm:acordeon"/>
    </p:tab>
</p:accordionPanel>

and there's the first lines of {#reporteOperacion}:

<composite:interface>
        <composite:attribute name="reporteOperacionDto" required="true" />
        <composite:attribute name="contenedorId" required="true" />
        <composite:attribute name="formId" required="true" />
    </composite:interface>

    <composite:implementation>

        <p:outputPanel id="panelGeneral" >

            <fieldset>
                <legend>Reporte 
                    <h:outputText value="#{cc.attrs.reporteOperacionDto.metaArchivoReporte.fecha}" >
                        <f:convertDateTime pattern="dd/MM/yyyy" timeZone="GMT-4" />
                    </h:outputText>
                </legend>

来源：https://stackoverflow.com/questions/13770951/accordion-panel-appears-open-but-doesnt-show-content