base\View $renderers

A list of available renderers indexed by their corresponding supported file extensions. Each renderer may be a view renderer object or the configuration for creating the renderer object. For example, the following configuration enables both Smarty and Twig view renderers:

[
    'tpl' => ['class' => 'yii\smarty\ViewRenderer'],
    'twig' => ['class' => 'yii\twig\ViewRenderer'],
]

If no renderer is available for the given view file, the view file will be treated as a normal PHP and rendered via renderPhpFile().