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Olá a todos, tenho uma aplicação pequena, que roda normalmente no php5 porém ao mudar a versão do php para 7 a mesma está apresentando a seguinte mensagem de erro Notice: Trying to access array offset on value of type null in <?php /* * APP CORE CLASS * Creates URL & Loads Core Controller * URL Format - /controller/method/param1/param2 */ class Core { // Set Defaults protected $currentController = 'Pages'; // Default controller protected $currentMethod = 'index'; // Default method protected $params = []; // Set initial empty params array public function __construct(){ $url = $this->getUrl(); // Look in controllers folder for controller if(file_exists('../app/controllers/'.ucwords($url[0]).'.php')){ // If exists, set as controller $this->currentController = ucwords($url[0]); // Unset 0 index unset($url[0]); } // Require the current controller require_once('../app/controllers/' . $this->currentController . '.php'); // Instantiate the current controller $this->currentController = new $this->currentController; // Check if second part of url is set (method) if(isset($url[1])){ // Check if method/function exists in current controller class if(method_exists($this->currentController, $url[1])){ // Set current method if it exsists $this->currentMethod = $url[1]; // Unset 1 index unset($url[1]); } } // Get params - Any values left over in url are params $this->params = $url ? array_values($url) : []; // Call a callback with an array of parameters call_user_func_array([$this->currentController, $this->currentMethod], $this->params); } // Construct URL From $_GET['url'] public function getUrl(){ if(isset($_GET['url'])){ $url = rtrim($_GET['url'], '/'); $url = filter_var($url, FILTER_SANITIZE_URL); $url = explode('/', $url); return $url; } } } Alguém poderia dar uma força ai?