我有实体Super的SuperType表单。在这个表单中,我有一个collection字段为ChildType实体Child的表单类型super类型类:publicfunctionbuildForm(FormBuilderInterface$builder,array$options){$builder->add('childrens','collection',array('type'=>newChildType(null,array('my_custom_option'=>true)),}类子类:publicfunctionbuildForm(FormBuilderInterfac