How to display the variable I created (Opencart) on the page? What is responsible for displaying variables in the common/header.tpl file?

Question

PHP

I need to display the name of the new (logged in) client in header.tpl. The first step I decided to go to the controller and create a variable there with random content, display it on the page. In the controller, looking at how other variables are set, I write:

$data['customer_name'] = 'Sergey';
или
$this->data['customer_name'] = 'Sergey';

I output it like echo $customer_name; in tpl. At the output I get:

Undefined variable: customer_name in /vqmod/vqcache/vq2-catalog_view_theme_default_template_common_header.tpl

I take any other variable from the controller, which is set in the same way - everything is good.
Files I edit: catalog/view/theme/default/template/common/header.tpl
/catalog/controller/common/header.php
What did I do wrong?
PS There are suspicions that not only the header.php from the controller is responsible for the output of variables in this tpl file. From where else can variables be set in this case?

Answer 1

First, tell me what version of OpenCart

Answer 2

the error
Undefined variable: customer_name in /vqmod/vqcache/ ...
says that you should clear the cache, i.e. delete contents of vqcache

Answer 3

So how was the issue resolved? Same problem!

Answer 4

In header.php

if ($this->customer->isLogged()) {
  $data['welcome_message'] = sprintf("Добро пожаловать, %s!", $this->customer->getFirstName());
    }

In header.tpl

<div><?php if (isset($welcome_message)) { echo $welcome_message; } ?></div>