ZF2 use view helper in Validator class - localization

Question

UPDATED!
ZF2, l10n view helper. I can't understand how to use my view helper inside of a class.
I want to use it like: $this->t('STRING TO TRANSLATE');
example bellow
NB! i'm only localizing project, i'm not allowed to change code structure or smth like that.Also i'm absolute newb in ZF2.
my Class -
class Project extends InputFilter{
as i understood i have to implement ServiceLocatorAwareInterface interface, tried this:
use Zend\ServiceManager\ServiceLocatorInterface as ServiceLocator;
class Project extends InputFilter implements ServiceLocator
{
protected $services;
public function __construct(Connection $p4, $mode, ServiceLocator $services)
{
$this->services = $services;
//some code
$this->add(...);
$this->add(
array(
'name' => 'name',
'filters' => array('trim'),
'validators' => array(
array(
'name' => 'NotEmpty',
'options' => array(
'message' => "Name is required and can't be empty."
)
),
array(
'name' => '\Application\Validator\Callback',
'options' => array(
'callback' => function ($value) use ($p4, $toId, $mode, $reserved) {
$id = $toId($value);
if (!$id) {
return $this->t('STRING TO TRANSLATE');
}
// more code here
return true;
}
)
)
)
)
);
//some code
$this->add(...);
}
public function setServiceLocator(ServiceLocatorInterface $serviceLocator) {
$this->serviceLocator = $serviceLocator;
}
public function getServiceLocator() {
return $this->serviceLocator;
}
//how to get this method work ???
public function t($msg) {
$translate = $this->services->get('ViewHelperManager')->get('t');
return $translate($msg);
}
}
Usage in Controller:
use Projects\Filter\Project as ProjectFilter;
...
protected function doAddEdit($mode, $project = null)
{
$p4Admin = $this->getServiceLocator()->get('p4_admin');
$request = $this->getRequest();
// process add request.
if ($request->isPost()) {
// pull out the data
$data = $request->getPost();
// configure our filter with the p4 connection and add/edit mode
$filter = new ProjectFilter($p4Admin, $mode); //
$filter->setData($data);
// if the data is valid, setup the project and save it
$isValid = $filter->isValid();
if ($isValid) {
$values = $filter->getValues();
$project = new Project($p4Admin);
$project->set($values)
->save();
}
return new JsonModel(
array(
'isValid' => $isValid,
'messages' => $filter->getMessages(), // THESE array of messages i want to localize
'redirect' => '/projects/' . $filter->getValue('id')
)
);
}
// prepare view for form.
$view = new ViewModel;
$view->setVariables(
array(
'mode' => $mode,
'project' => $project ?: new Project
)
);
return $view;
}
What am i doing wrong ?

Answer 1

You're calling tr method inside a class constructor. tr method calls $this->getServiceLocator(). $this->getServiceLocator() will not return a service locator instance since it'll only be injected by service manager after it has created the object that implements ServiceLocatorAwareInterface.
So you'd have to pass a service locator instance to the constructor, or don't depend on it in your __construct method. Probably the easiest way to go is to move your code from the constructor to the init method. Init is supposed to get called automatically as long as you get your input filter through the InputFilterManager.
Also I don't think you need the translator view helper. You should be able to get it from the service manager like so: $serviceManager->get('translator')

Answer 2

There is no need to do this at all the validation message will be translated by the validator anyway. But your config is a bit wrong I think
$this->add(
array(
'name' => 'name',
'filters' => array('trim'),)
'validators' => array(
array(
'name' => 'NotEmpty',
'options' => array(
'messages' => array(
\Zend\Validator\NotEmpty::IS_EMPTY => 'YOUR_TRANSLATION_STRING_IS_EMPTY',
\Zend\Validator\NotEmpty::INVALID => 'YOUR_TRANSLATION_STRING_INVALID',
)
)
)
),
Have a read of https://zf2-docs.readthedocs.org/en/latest/modules/zend.validator.html#translating-messages
You will need to ensure you are managing your dependencies correctly for this to work so really depends how you are using the input filter.
If your not directly adding to a form or using InputFilterAwareInterface on your model you'll need to make sure your InputFilter is registered with InputFilterPluginManager and you retrieve it using InputFilterPluginManager rather than instantiating directly