eventTypeInput = new TextField<String>( "eventTypeInput", new PropertyModel<String>( this, "eventType" ) );
add( eventTypeInput.setRequired( true ).setLabel( Model.of( "Event Type" ) ).setOutputMarkupId( true ) );
eventTypeSelector = new DropDownChoice<String>( "eventTypeSelector",
new PropertyModel<String>( this, "eventTypeSelected" ),
fetch.eventTypes() );
eventTypeSelector.add( new AjaxFormComponentUpdatingBehavior( "onchange" )
{
@Override
protected void onUpdate( AjaxRequestTarget target )
{