What is the Asynchronous format to to use "Loading a Subset of Related Child Objects" ?

I have 2 tables :Category and QuestionperCategory ,
-the relation is one to many, each category has objectId by default
I’m using the following code, but when I populate my listview I get nothing
//
StringBuilder whereClause = new StringBuilder();
whereClause.append( “Categoria[pregunta_por_categoria]” );
whereClause.append( “.objectId=’” ).append( recover_objectId ).append( “’” );
whereClause.append( " and " );
whereClause.append( “preguntas” );
BackendlessDataQuery dataQuery = new BackendlessDataQuery();
dataQuery.setWhereClause( whereClause.toString() );
Backendless.Persistence.of(Pregunta_por_categoria.class).find(dataQuery, new AsyncCallback<BackendlessCollection<Pregunta_por_categoria>>()
{
@Override
public void handleResponse(BackendlessCollection<Pregunta_por_categoria> response) {

}
@Override
public void handleFault(BackendlessFault fault) {
}
});

Hi @Jonathan Mamani Herrera,
You have to populate Listview with data from handleResponse(BackendlessCollection<Pregunta_por_categoria> response) method. You can save response to some outer field or refresh Listview in handleResponse section.
Regards, Artur

Thanks for your support I will try according to your advice,but I want to be sure if the format I wrote above is the corect format for "Loading a Subset of Related Child of Objects,please I’d feel quiet if you make me sure this doubt.
Thanks a lot

Do you mean using StringBuilder for building queries? If I were you I would use String.format() instead.
Hope that helps.
Artur.