In many systems I have noticed that there are global variables in JS that are
placed in the head with the translations. There is a technique to work with
thereby?
Make it clear: This is not a tutorial. You must know by now framework, and I’ll just exemplify the passage of a variable from $_SESSION to the JavaScript using the native tools of Codeigniter. I didn’t care much for safety either, but I don’t think there’s any gross flaw in that code.
The goal is for you to understand how to assign session data PHP to a variable JavaScript, which, if I understand correctly, answers your question. That is, we will manipulate the value of the variable JavaScript as amended in PHP.
So use Sessions, Hooks and helpers. The hook will set the default session value for the variable. O helper will recover this value to the Javascript and print in the document HTML.
- Enable use of session library:
I like autoload: get into application/config/autoload.php and insert Session in the array correspondent: $autoload['libraries'] = array('session').
- Defining available languages:
These data can, logically, be loaded from your database. In the example I will define the array $config['langs'] to serve as a reference. Enter application/config/config.php and insert this: $config['langs'] = ['pt-br','en','es'];.
Thus, these are the only hypotheses available for the method set_lang_var() that defines the language.
- Enable and create a hook:
Enable the use of Hooks defining $config['enable_hooks'] = TRUE; in the archive application/config/config.php;
Within application/config/hooks.php insert the following:
$hook['post_controller_constructor'][] = array(
'function' => 'set_lang',
'filename' => 'set_lang.php',
'filepath' => 'hooks'
);
Now create the hook application/hooks/set_lang.php and insert the following:
<?php
defined('BASEPATH') OR exit('No direct script access allowed');
function set_lang() {
$ci = & get_instance();
//$ci->session->unset_userdata('lang');
if(NULL == $ci->session->userdata('lang')){
//Se nao houver idioma na session, define o idioma padrao
$userdata = ['lang'=>'pt-br'];
$ci->session->set_userdata($userdata);
}
//Caso contrario, o metodo teste/set_lang_var() pode ser usado para mudar o idioma
}
From this point on PHP already know which is the default language. Now it will be necessary to make the system pass the data of $_SESSION of PHP for a variable JavaScript readable.
- Enabling and creating a helper:
To use the helpers you must carry them. I like to use autoload: inside application/config/autoload.php add the helper string at the array appropriate: $autoload['helper'] = array('string');
It is good practice not to change the original scripts of framework, then stretching the helper to be able to work without fear: create the file application/helpers/MY_string_helper.php and insert the following:
<?php
defined('BASEPATH') OR exit('No direct script access allowed');
if (!function_exists('string_lang')) {
function string_lang(){
$ci = & get_instance();
echo '<script type="text/javascript">';
echo "var lang='".$ci->session->lang."'";
echo "</script>\n";
}
}
- Controller, methods and view:
The controller application/controllers/Teste.php has two very simple methods:
<?php
defined('BASEPATH') OR exit('No direct script access allowed');
class Teste extends CI_Controller {
function get_lang_var(){
$data['title'] = 'get_lang_var()';
$this->template_action = strtolower(__CLASS__."/".__FUNCTION__);
$this->load->view($this->template_action, $data);
}
function set_lang_var(){
$lang = $this->uri->segment(3, 0);
$userdata = ['lang'=>$lang];
if(in_array($lang, $this->config->item('langs'))){
$this->session->set_userdata($userdata);
redirect('teste/get_lang_var');
}
else{
redirect('teste/set_lang_var/pt-br');
}
}
}
To view application/views/teste/get_lang_var.php is also quite simple:
<?php defined('BASEPATH') OR exit('No direct script access allowed'); ?>
<?= doctype('html5'); ?>
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8"/>
<title><?= $title ?></title>
<base href="<?= config_item('base_url') ?>">
<?=string_lang()?>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" integrity="sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M" crossorigin="anonymous">
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.11.0/umd/popper.min.js" integrity="sha384-b/U6ypiBEHpOf/4+1nzFpr53nxSS+GLCkfwBdFNTxtclqqenISfwAzpKaMNFNmj4" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/js/bootstrap.min.js" integrity="sha384-h0AbiXch4ZDo7tp9hKZ4TsHbi047NrKGLO3SEJAg45jXxnGIfYzk4Si90RDIqNm1" crossorigin="anonymous"></script>
<style>body{padding-top: 20px;}</style>
</head>
<body>
<div class="container">
<p>Mude o idioma: <?=$_SESSION['lang']?></p>
<?=anchor('teste/set_lang_var/pt-br', 'pt-br')?>
<?=anchor('teste/set_lang_var/en', 'en')?>
<?=anchor('teste/set_lang_var/es', 'es')?>
</div>
</body>
</html>
Watching the browser console (or the page’s source code) will be possible to realize that the variable <script type="text/javascript">var lang='pt-br'</script> changes value whenever you choose a new language.
That’s it. Study this code and you’ll get a sense of how to do it in other ways, or apply the concept to the libraries you’re using.