display form error messages underneath the input fields Phalcon php - php

Question

Is there a way to display error messages underneath the input fields of a form if a field didn't pass validation? Can I somehow process form in the same action (User/index in my case) that the form is displayed and then send those error messages to view? What I have is : index.volt:
<div class="loginForm">
<form action=<?= $form->getAction(); ?> method="POST">
<label for="username">Username: </label>
<?= $form->render('username'); ?>
<br/>
<label for="password">Password: </label>
<?= $form->render('password'); ?>
<br>
<?= $form->render('login'); ?>
</form>
</div>
LoginForm.php:
<?php
use Phalcon\Forms\Form,
Phalcon\Forms\Element\Text,
Phalcon\Forms\Element\Password,
Phalcon\Forms\Element\Submit,
Phalcon\Validation\Validator\PresenceOf,
Phalcon\Validation\Validator\StringLength;
class LoginForm extends Form {
public function initialize()
{
$this->setAction('login');
$username = new Text('username');
$username->addValidator(new PresenceOf(array (
'message' => 'Can\'t be empty'
)));
$password = new Password('password');
$password->addValidator(new PresenceOf(array (
'message' => 'Can\'t be empty'
)));
$submit = new Submit('login', array('value' => 'Login'));
$this->add($username);
$this->add($password);
$this->add($submit);
}
}
And UserController.php:
<?php
class UserController extends \Phalcon\Mvc\Controller
{
/**
* login form
* #var LoginForm
*/
private $_loginForm;
public function initialize()
{
$this->_loginForm = new LoginForm();
}
public function indexAction()
{
$this->view->setVar('form', $this->_loginForm);
}
public function loginAction()
{
if($this->request->isPost()) {
if (!$this->_loginForm->isValid($this->request->getPost())) {
foreach ($this->_loginForm->getMessages() as $message) {
echo $message. '<br />';
// redirect to User/index and pass error messages to view to display them to a user
}
}
}
}
}
EDIT:
Or it would be even better to process this form on the same action that it is displayed. How can I do this?

Answer 1

First, what you have provided in your index.volt isn't volt content. See here how to configure Volt and use the Volt language in your views.
What you're asking for is called flashing messages in Phalcon.
Unfortunately, in the current version you can just flash messages based on type(success, error, warning, etc.) but you can create your own type, so let's fake that the type means the input name.
UserController.php
...
public function loginAction()
{
if($this->request->isPost()) {
if (!$this->_loginForm->isValid($this->request->getPost())) {
$messages = $this->_loginForm->getMessages();
$userMessage = $messages->filter('username');
if(count($userMessage))
$this->flash->message('username', $userMessage[0]);
$passMessage = $messages->filter('password');
if(count($passMessage))
$this->flash->message('username', $passMessage[0]);
return $this->dispatcher->forward(["action" => "index"]);
} else {
//Login
}
}
index.volt
<div class="loginForm">
<form action="{{form.getAction()}}" method="POST">
<label for="username">Username: </label>
{{form.render('username')}}<br/>
{{ flash.has('username') ? flash.output('username') : '' }}
<label for="password">Password: </label>
{{form.render('password')}}<br>
{{ flash.has('password') ? flash.output('password') : '' }}
{{form.render('login')}}
</form>
</div>