CodeIgniter 4 - How to display Flashdata inside a View? - php

Question

I'm upgrading my project from CodeIgniter 3 to CodeIgniter 4,
I'm trying to display a flashdata message inside a view but unfortunately I get differents error for each method I try.
In CodeIgniter 3, I used to call something like:
<?php if ($this->session->flashdata('message')) : ?>
<div class="alert alert-success alert-dismissible fade show" role="alert">
<?php echo $this->session->flashdata('message'); ?>
<button type="button" class="close" data-dismiss="alert" aria-label="Close"><span aria-hidden="true">×</span></button>
</div>
<?php endif; ?>
I try the same in CodeIgniter 4 but I get this error:
ErrorException
Undefined property: CodeIgniter\View\View::$session
Can any one show me how to achieve this ?
Thanks in advance.

Answer 1

You can use session() function directly:
<?php if (session()->getFlashdata('message') !== NULL) : ?>
<div class="alert alert-success alert-dismissible fade show" role="alert">
<?php echo session()->getFlashdata('message'); ?>
<button type="button" class="close" data-dismiss="alert" aria-label="Close"><span aria-hidden="true">×</span></button>
</div>
<?php endif; ?>

Answer 2

The context ($this) is an instance of the View class --> you don't have access to the Session instance directly
You can create new instance below
$session = \Config\Services::session();

Answer 3

In CodeIgniter 4 the new way to set Flash data $session->setFlashdata('item', 'value'); and to view $session->getFlashdata('item');
You can check it out here : Set Flash data in session in CodeIgniter

Answer 4

I just use another way to display a flashdata and it works fine.
In my controller, I added a new index to the data passed to the view:
$data['message'] = "Sorry, you must login first";
return view('login', $data);
Then in the view login.php I call it like this:
<?php if (isset($message)) : ?>
<div class="alert alert-warning alert-dismissible fade show" role="alert">
<?php echo $message; ?>
<button type="button" class="close" data-dismiss="alert" aria-label="Close"><span aria-hidden="true">×</span></button>
</div>
<?php endif; ?>
UPDATE:
I just use the markAsFlashdata() method and It works perfectly. Here's what I did in the controller just before the return method:
$_SESSION['error'] = 'Sorry, you must login first';
$session = session();
$session->markAsFlashdata('error');
Then in the view I access the flashdata using $_SESSION['error']:
<?php if (isset($_SESSION['error'])): ?>
<div class="alert alert-warning" role="alert">
<?= $_SESSION['error']; ?>
</div>
<?php endif;?>

Answer 5

Add this line just after echo $this->section('content');
$session = \Config\Services::session();
<?php if (isset($message)) : ?>
<div class="alert alert-warning alert-dismissible fade show" role="alert">
<?php echo $message; ?>
<button type="button" class="close" data-dismiss="alert" aria-label="Close"><span aria-hidden="true">×</span></button>
</div>
<?php endif; ?>

Answer 6

For now my solution has been to create a view method in BaseController.php.
The idea is to add more "common" info into the $data array.
/* In BaseController.php */
/**
* view function replaced
*/
public function view(string $name, array $data = [], array $options = []): string
{
// Inject global data
$data = array_merge($data,["controller" => $this]);
return view($name,$data,$options);
}
/**
* Temporary message
*/
public function flash($message, $type = 'info') {
$this->session->setFlashdata('flash_message',
["message" => $message, "type" => $type]);
}
public function getFlash() {
return $this->session->getFlashdata('flash_message');
}
/* In the descendant controller */
return $this->view('products/list',['products' => $products]);
/* In the view */
<div id="messages">
<?php if($flash = $controller->getFlash()) : ?>
<?= view_cell('Base::alert', $flash); ?>
<?php endif ?>
</div>