Dependent checkbox

Question

I have a problem and I was wondering if you could help me.

I have a CRUD that registers cycles, these cycles can have many courses.

What I wanted to do exactly, is validate the selectsOneRadios when registering a question, ie, choose a cycle in a checkbox and in the next checkbox enable the user to register a question of a course that is of this chosen cycle. It is more or less, check box of State and City.

Follows the code:

Questaobean

@Named
@ViewScoped
public class CadastroUsuarioBean implements Serializable {

    private static final long serialVersionUID = 1L;

    @Inject
    private UsuarioService usuarioService;

    @Inject
    private GrupoDAO grupoDAO;

    @Inject
    private CursoDAO cursoDAO;

    @Inject
    private FormacaoDAO formacaoDAO;

    private Usuario usuario;
    private List<Grupo> grupos;
    private List<Curso> cursos;
    private List<Formacao> formacoes;


    @PostConstruct
    private void init() {
        this.limpar();
        this.grupos = grupoDAO.buscaPorTodosGrupos();
        this.cursos = cursoDAO.buscaPorTodosCursos();
        this.formacoes = formacaoDAO.buscaPorTodasFormacoes();


    }

    @Transactional
    public void salvar() throws Exception {
        try {
            this.usuarioService.salvar(usuario);
            FacesUtil
                    .addSuccessMessage("Pré cadastro efetuado com sucesso. Aguarde a aprovação!");
        } catch (IllegalArgumentException e) {
            FacesUtil.addErrorMessage("Erro ao tentar realizar o cadastro!");
        }
        this.limpar();
    }

    private void limpar() {
        this.usuario = new Usuario();
    }

    public List<Grupo> getGrupos() {
        return grupos;
    }

    public List<Curso> getCursos() {
        return cursos;
    }

    public List<Formacao> getFormacoes() {
        return formacoes;
    }

    public Usuario getUsuario() {
        return usuario;
    }

    public void setUsuario(Usuario usuario) {
        this.usuario = usuario;
    }

DAO:

@SuppressWarnings("unchecked")
public List<Curso> buscarCursoPorCiclo(Long codigo) {
    return  manager
            .createQuery(
                    "select c from Ciclo c JOIN c.cursos a where c.codigo = ?")
            .setParameter(1, codigo).getResultList();
}

Page XHTML:

<h:panelGrid id="cicloPanelGrid" columns="2">
                    <p:outputLabel value="Ciclo" for="ciclo" style="font-weight:bold" />
                    <p:selectOneMenu id="ciclo"
                        value="#{cadastroQuestaoBean.questao.ciclo}"
                        converter="cicloConverter" required="true"
                        requiredMessage="Preencha o Ciclo">
                        <p:ajax event="change" process="@this ciclo" update="curso" />
                        <f:selectItem itemLabel="Selecione..." />
                        <f:attribute name="collectionType" value="java.util.ArrayList" />
                        <f:selectItems value="#{cadastroQuestaoBean.ciclos}" var="ciclo"
                            itemLabel="#{ciclo.descricao}" itemValue="#{ciclo}" />
                    </p:selectOneMenu>
                </h:panelGrid>

                <h:panelGrid columns="2">
                    <p:outputLabel value="Curso" for="curso" style="font-weight:bold" />
                    <p:selectOneMenu  id="curso" 
                        value="#{cadastroQuestaoBean.questao.curso}"
                        converter="cursoConverter" required="true"
                        requiredMessage="Preencha o curso">
                        <f:selectItem itemLabel="Selecione..." />
                        <f:attribute name="collectionType" value="java.util.ArrayList" />
                        <f:selectItems value="#{cadastroQuestaoBean.cursos}" var="curso"
                            itemLabel="#{curso.nome}" itemValue="#{curso}" />
                    </p:selectOneMenu>
                </h:panelGrid>

ERROR:

itemLabel="#{curso.nome}": Property 'nome' not found on type com.sisEnade.tcc.modelo.Ciclo