Alternative $this->config>set_item($item, $value)

All the config files are classes where all the properties are public. That means that once you create an instance of a config you can modify the properties however you see fit.

PHP Code:

<?php namespace App\Controllers;

use Config;

class Home extends BaseController
{
    public function index()
    {
       $viewConfig = new Config\View();
       $viewConfig->saveData = false;
       // do stuff
      }
} 


You can dynamically add properties to the class

PHP Code:

$config = new Config\App();
$config->adHoc = ["Hello ", "World", "!"];
foreach ($viewConfig->adHoc as $value)
{
    echo $value;  // Hello World!
}