Array-type property and Form CollectionType with data transformer - forms

Question

I have an entity with a property that is set as an array
/**
* #ORM\Column(type="array")
*/
private $labels = [];
this array of data stores translations of a label like
[
'en' => 'foo-in-English',
'de' => 'foo-in-German',
'ru' => 'foo-in-Russian'
]
I have a Form with the type set for the labels like:
$builder
->add('labels', CollectionType::class);
Note that the entry_type defaults (properly) to TextType here. Left as is, the template would be displayed with text fields, like:
Labels: en: _____FOO IN ENGLISH____
de: _____FOO IN GERMAN_____
ru: _____FOO IN RUSSIAN____
But, I would like the fields to be displayed with the actual language name and not the two-letter code as the label, so something like:
Labels: English: _____FOO IN ENGLISH____
German: _____FOO IN GERMAN_____
Russian: _____FOO IN RUSSIAN____
I also want to make sure that all my selected/supported languages are displayed - even if they currently have no value.
So, this seems like the proper place for a DataTransformer, but try as I might I could not get this concept to work within the Form class. It seems that attempting to transform the data of a collection type is more difficult (or impossible?) than a simpler type like text.
I've overcome this as a workaround by transforming the data within the controller before submitting it to the form and after processing the form before persistence. e.g.
$this->transformTranslations($fooEntity);
$form = $this->createForm(FooType::class, $fooEntity);
$form->handleRequest($request);
if ($form->isSubmitted() && $form->isValid()) {
$fooEntity = $form->getData();
$this->reverseTransformTranslations($fooEntity);
$this->getDoctrine()->getManager()->persist($fooEntity);
$this->getDoctrine()->getManager()->flush();
...
I'm wondering if anyone has a better method (like how to use normal data or model transformers). I can't seem to find much online about using data transformers with collection types. TIA!

Answer 1

I have not personally used a doctrine array value before, however
you can define a 'default' form class for each of your translation options like so:
AppBundle\Form\LanguageStringEditorType.php
class LanguageStringEditorType extends AbstractType {
public function buildForm(FormBuilderInterface $builder, array $options) {
$builder
->add('en', TextareaType::class, ['label' => 'English'])
->add('de', TextareaType::class, ['label' => 'German'])
->add('ru', TextareaType::class, ['label' => 'Russian'])
;
}
}
If you keep the naming ('en', 'de' and 'ru') the same as your data array key names for example having an (doctrine) entity like this:
AppBundle\Entity\LanguageString.php
class LanguageString {
private $identifier;
private $translations; // this is the doctrine array type
// however I didn't feel like setting up a database for this
// test so I'm manually filling it see the next bit
... Getter and setter things ...
And create a type for that as well:
AppBundle\Form\LanguageStringType.php
class LanguageStringType extends AbstractType {
public function buildForm(FormBuilderInterface $builder, array $options) {
$builder
->add('identifier')
->add('translations', LanguageStringEditorType::class, ['label' => 'Translations'])
;
}
}
We can use this in the controller
$data = new LanguageString();
// fill some dummy content (not using database)..
$data->setIdentifier('hello_world');
$data->setTranslations([
'en' => 'Hello world!',
'de' => 'Hallo Welt!',
'ru' => 'Привет мир'
]);
$form = $this->createForm(LanguageStringType::class, $data);
return $this->render('default/index.html.twig', [
'form' => $form->createView()
]);
And the rest is done by magic, no transformers required. The data is placed in the form fields. And set to the entity when using the handleRequest. Just remember that the data key values are the same as the form builder names.
And as a bonus you have defined all your default language fields in the LanguageStringEditorType class, filled in or not.

Answer 2

So, I learned I needed to separate my two needs into different solutions. First I created a new form type to use instead of the text type I was using by default:
$builder
])
->add('labels', CollectionType::class, [
'entry_type' => TranslationType::class
])
This class is very simple and is only an extension of a regular TextType:
class TranslationType extends AbstractType
{
/**
* #var LocaleApiInterface
*/
private $localeApi;
/**
* TranslationType constructor.
* #param LocaleApiInterface $localeApi
*/
public function __construct(LocaleApiInterface $localeApi)
{
$this->localeApi = $localeApi;
}
/**
* {#inheritdoc}
*/
public function buildView(FormView $view, FormInterface $form, array $options)
{
$view->vars['label'] = array_search($view->vars['name'], $this->localeApi->getSupportedLocaleNames());
}
public function getParent()
{
return TextType::class;
}
}
This satisfied the labelling issue. Second, to ensure I had all the supported locales in my data, I used a FormEventListener:
$builder->addEventListener(FormEvents::PRE_SET_DATA, function (FormEvent $event) {
$supportedLocales = $this->localeApi->getSupportedLocales();
$data = $event->getData();
$labels = $data['labels'];
foreach ($supportedLocales as $locale) {
if (!array_key_exists($locale, $labels)) {
$labels[$locale] = $labels['en'];
}
}
$data['labels'] = $labels;
$event->setData($data);
});
This adds the required keys to the data if they are not already present.