Custom 404 Page in Slim Framework 3

In the past month, I've been learning Slim 3 PHP framework through a website as a real experiment of how powerful Slim Framework is. In this post, I'm sharing a code snippet for rendering 404 page.

Between creating a Slim Container and creating the Slim App, I override the default notFoundHandler.

$container = new Slim\Container;

...

// Override the default Slim Not Found Handler
$container['notFoundHandler'] = function ($c) {
    return function ($request, $response) use ($c) {
        return $c['view']->render($response, '404.html', [])->withStatus(404);
    };
};

...

// Initialize the app
$app = new Slim\App($container);

In my case, I use Twig template engine for views. If your case is different, change the render line.