performanceChoice.add(new AjaxFormComponentUpdatingBehavior("onchange") {
@Override
protected void onUpdate(final AjaxRequestTarget target)
{
final short pos = position.getNumber();
final PeriodOfPerformanceType s = performanceChoice.getModelObject();
final boolean visible = s.equals(PeriodOfPerformanceType.OWN);
setPosPeriodOfPerformanceVisible(pos, visible);
if (ajaxPosTargets != null) {
for (final Component ajaxPosTarget : ajaxPosTargets)
target.add(ajaxPosTarget);
}