Custom Controller to switch templates

gistfile1.php

<?php
namespace My\Custom\Controller; 

use Bolt\Controllers\Frontend as BoltFrontend; 

class  Frontend extends BoltFrontend {

    public function record(Request $request, $contenttypeslug, $slug = '') 
    {
        parent::record($request, $contenttypeslug, $slug);
        if (condition) {
            $template = 'xxxxxx';
        } else {
            $template = 'xxxxxx';
        }
        $globals = [
            'record'                      => $content,
            $contenttype['singular_slug'] => $content
        ];

        return $this->render($template, [], $globals);
    }
    
}