Did you define the translations in the forms domain?

@xabbuh It's the same translation unit id which already exist in the demo.
I tried with "form" and "form+intl-icu",it's not working.

I did not tried to create a new translation file : "form.xlf", but i assume the system should use the proper domain.

edit : my bad, i though the domain was "form" but in the demo, it's in "messages" and it's working now.

I have the same issue (not translated) in my personal project. I will look deeper since it's working in the demo.

Sorry for that.

Thanks

Finally after testing on demo project :

            ->add('title', null, [
                'attr' => ['autofocus' => true],
                'label' => new TranslatableMessage('label.title',[], 'messages'),
				'data'       => new TranslatableMessage('label.title',[], 'messages'),
				
            ])

The "data" display the value "label.title" instead of translation
It's not working neither with a ChoiceType with "attr/placeholder"

Can you create a small example application that allows to reproduce your issue?

data is not something that gets translated, so passing a TranslatableMessage here is not expected to work.

Hi @stof

I can understand your point but it's a limiting the feature, no ?

In my case :
I have a page to edit Taxonomy. In that page i display trans_unit_id, the English translation and user can choose to a parent is needs.
The field English translation is non-mapped obviously. To display the proper information in this field, i do a simple translatableMessage of the current Taxonomy->getTransUnitId().
So, i display this field for information (it's not editable by user for now)

@xabbuh For the exemple, you can added in PostType of the demo symfony project :

            ->add('choice', EntityType::class, [
                'label' => 'label.tags',
				'choice_label'  => function ($choice, $key, $value) {

					return new TranslatableMessage('label.title',[], 'messages');
				},
				'class'         => Post::class,
				'mapped' => false,
				'attr' =>
				[
				'data-placeholder' => new TranslatableMessage('label.title',[], 'messages')
				]
            ])

"data-placeholder" does not display the translated value
"choice_label" does not translate too

A TranslatableMessage still needs to be passed to the translator to actually produce a translated string. This class cannot magically get access to the translator to produce a translated string (btw, that's the reason why this class is not stringable).

In your example, choice_label is not translated because EntityType disables the translation of choices by default (as those are generally user-provided values stored in your entity), contrary to the its parent type ChoiceType. If you re-enable the translation of choices, it will work (not that if you don't need to pass parameters, returning the translation key is enough, except maybe for detection by the extractor)

I did not know for the option "choice_translation_domain". Thanks :)
I enabled it and used TranslatableMessage (because i have to pass the specific domain which is not the default one) and "choice_label" is working :)
For the information, the code was just for the example, in my code, i'm using data from the entity which is a "trans_unit_id", hence the translation after.

I'm sorry i did not understand the first part of you answer. What class are you speaking about ?

Hey, thanks for your report!
There has not been a lot of activity here for a while. Is this bug still relevant? Have you managed to find a workaround?