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Ich versuche, die Formularfelder zurückzusetzen, nachdem ich in einem Dialogfeld die Schaltfläche "Bestätigen" gewählt habe

<h:form id="form">  
<p:panel id="panelform">
 <h:panelGrid id="formulaire" columns="2"> 
...
</h:panelGrid>
</p:panel>
 <p:dataTable ..... </p:dataTabe>
</h:form>
<p:confirmDialog style="position: absolute; width: 50px; border-color: blue" id="deleteData"  message="Your Database Will be completely removed. Are you sure? "  
                                     appendToBody="true"                                                               
                                     header="Delete List" severity="alert" widgetVar="deleteDialog">                          
                        <h:form>     
                            <p:commandButton id="confirm" value="Confirm" actionListener="#{MB.deleteData()}" update=":form" ajax="true" oncomplete="deleteDialog.hide(); purchase.hide();" >                            
                            </p:commandButton>  
                            <p:commandButton id="cancel" value="Later" onclick="deleteDialog.hide();" type="button" />                           
                        </h:form>
                    </p:confirmDialog> 

Meine deleteData-Methode in meiner sessionScoped-Bean lautet

 public String deleteData() {
    logger.log(Level.SEVERE, "*****delete Datas***** ");
    dataBusinessLocal.deletedatas(datas);
    logger.log(Level.SEVERE, "*****delete Data***** ");
    dataBusinessLocal.deleteData(data);
    datas.clear();
    RequestContext.getCurrentInstance().reset("form:panelform");  
    return "datasList";
}