return (FormCheckbox) new FormCheckbox(name, ((RubyBoolean) RubyHelper.getObj(holder, index)).isTrue())
.addChangeListener(new FormElementChangeListener() {
@Override
public void stateChanged(FormElement form) {
RubyHelper.setObj(holder, index, new RubyBoolean(RubyHelper.getRunTime(holder, index), Boolean.parseBoolean(form.getContentAsString())));
}
});
}