如何在Laravel中将变量传递给http错误布局？

Question

I am going crazy looking for a solution to this. I need to do a very simple thing - pass variables to the custom 404 page layout. Laravel lets you easily create a custom view for your http errors by creating a file like /resources/views/errors/404.blade.php but why doesn't it easily let you pass variables to it?

I tried overwriting app/Exceptions/Handler.php render method:

public function render($request, Exception $e)
    {
        if($this->isHttpException($e)){
            switch ($e->getStatusCode()) {
                case '404':
                      parent::render($request, $e)->flash();
                      $categories = Category::hierarchy();
                      return View::make('errors.404')->with(['categories' => $categories]);
                break;

                default:
                    return $this->renderHttpException($e);
                break;
            }
        }
        return parent::render($request, $e);
    }

But for whatever reason this doesn't work and I cannot access the categories variable in my master layout. I'm working on a site that displays header on error pages but if I can't pass variables to the error view then my header cannot be created.

Undefined variable: categories

Anyone has an idea of what could be going wrong? Is it just impossible to do this? I have read you can pass the exception in and get a message from it but what's the point of that? I don't want to have to duplicate the entire layout and rewrite all variables.

Answer 1

You're looking for a View Composer: https://laravel.com/docs/5.3/views#view-composers