我正在构建一个Symfony应用程序，并使用表单事件与一些jquery/ajax来完成“州/市/区”的选择。但是，我遇到了一个小问题。我正在使用格式"省份-> 城市-> 郊区"。据我所知我的代码没什么问题，但当执行到添加一个城市选择的监听器的部分时，它会抛出以下错误：
名称为 "physicalCity" 的子项不存在。
显然，当我尝试向新创建的字段添加事件侦听器时，它会发生这种情况，因此是在由事件侦听器创建的元素上添加事件侦听器？下面是代码的一部分... 我做错了什么？任何帮助将不胜感激！
public function buildForm(FormBuilderInterface $builder, array $options) {
$builder
->add('schoolName')
->add('physicalProvince', 'entity', array(
'mapped' => false,
'class' => 'MY\MainBundle\Entity\Province',
'empty_value' => 'Select a province',
'attr' => array(
'class' => 'province',
'data-show' => 'physical-city',
)
));
/*
* For the physical cities
*/
$physicalCityModifier = function(FormInterface $form, Province $province = null) {
if (null !== $province)
$cities = $province->getCities();
else
$cities = array();
$form->add('physicalCity', 'entity', array(
'mapped' => false,
'class' => 'MY\MainBundle\Entity\City',
'empty_value' => 'Select a province first',
'choices' => $cities,
'attr' => array(
'class' => 'city physical-city',
'data-show' => 'physical-suburb'
)
));
};
$builder->addEventListener(
FormEvents::PRE_SET_DATA,
function(FormEvent $event) use ($physicalCityModifier) {
$data = $event->getData();
if (is_object($data->getPhysicalSuburb()))
$province = $data->getPhysicalSuburb()->getCity()->getProvince();
else
$province = null;
$physicalCityModifier($event->getForm(), $province);
}
);
$builder->get('physicalProvince')->addEventListener(
FormEvents::POST_SUBMIT,
function (FormEvent $event) use ($physicalCityModifier) {
$province = $event->getForm()->getData();
$physicalCityModifier($event->getForm()->getParent(), $province);
}
);
/*
* For the physical suburbs
*/
$physicalSuburbModifier = function(FormInterface $form, City $city = null) {
if (null !== $city)
$suburbs = $city->getSuburbs();
else
$suburbs = array();
$form->add('physicalSuburb', null, array(
'choices' => $suburbs,
'empty_value' => 'Select a city first',
'attr' => array(
'class' => 'physical-suburb'
),
));
};
$builder->addEventListener(
FormEvents::PRE_SET_DATA,
function(FormEvent $event) use ($physicalSuburbModifier) {
$data = $event->getData();
if (is_object($data->getCity()))
$city = $data->getCity();
else
$city = null;
$physicalSuburbModifier($event->getForm(), $city);
}
);
$builder->get('physicalCity')->addEventListener(
FormEvents::POST_SUBMIT,
function(FormEvent $event) use ($physicalSuburbModifier) {
$city = $event->getForm()->getData();
$physicalSuburbModifier($event->getForm()->getParent(), $city);
}
);
}