Can't select value in af:selectBooleanCheckbox

Question

I have a query where i bring a column from this part of my query:
DECODE((SELECT GR.GESDOPCCOD FROM GESDROL GR
WHERE GR.GESDOPCCOD=GO.GESDOPCCOD
AND(:PV_CODROL IS NOT NULL AND GR.GESDROLCOD=:PV_CODROL)),NULL,'NoRegistrado','Registrado')REGISTRADO
I drag and drop it from the data control as a selectBooleanCheckbox. So if the query returns "Registrado" then the selectBooleanCheckBox has to be selected. I do it like this:
<af:selectBooleanCheckbox selected="#{row.Registrado=='Registrado'}"
id="sbcReg"/>
The results are ok, the problem is that i can`t not select or deselect, even though in the ViewObjec the attribute has the property : IsUpdatable="true"

Answer 1

I modify the query to return true or false as string and i can select the value of <af:selectOneBooleanCheckbox>
SELECT GO.GESDOPCCOD
,GO.GESDOPCACH
,GO.GESDOPCNVL
,GO.GESDOPCRUT
,DECODE((SELECT GR.GESDOPCCOD FROM GESDROL GR
WHERE GR.GESDOPCCOD=GO.GESDOPCCOD
AND(:PV_CODROL IS NOT NULL AND GR.GESDROLCOD=:PV_CODROL)),NULL,'false','true')REGISTRADO
FROM GESDCOPC GO
WHERE GO.GESDOPCTIP='C'
and in my view:
<af:selectBooleanCheckbox value="#{row.Registrado}"/>
The problem i have know is that when i chek the value of my selectOneBooleanCheckBox, i update my model with this:
CollectionModel model = (CollectionModel) tcarp.getValue();
JUCtrlHierBinding bind = (JUCtrlHierBinding) model.getWrappedData();
Row[] rows = bind.getAllRowsInRange();
if((Boolean)valor){
rows[pos].setAttribute("Registrado", "true");
}else{
rows[pos].setAttribute("Regitrado, "false");
But when i click in my commandButton to save it, when i do: row[pos].getAttribute("Registrado") to get the value of the selectOneBooleanChekBox, it returns null. It is like the column has been deleted.