PHP8 problems

Hi, im using ci4 and working well other php versions but i have problem with php8.
first problems solved with here: https://forum.codeigniter.com/thread-78146.html
and now my route not working. 

PHP Code:

$routes->get('/', 'IndexController::index'); 


and getting this error: Controller method is not found: index
so if i do my index function static route working like this. But i cant all functions to static please help.

PHP Code:

<?php namespace App\Controllers;
class IndexController extends BaseController
{
  public function __construct(){
    var_dump("TEST");
  }
public static function index()
{
return view('welcome_message');
}
//--------------------------------------------------------------------

} 


i just deleted xampp and loaded 7.4php version.

Because PHP 8.0.0 is not yet compatible with CodeIgniter 4. Switch to PHP 7.4.13.

What did you Try? What did you Get? What did you Expect?

Joined CodeIgniter Community 2009.  ( Skype: insitfx )