2.2.3 Rendering an Action’s Template from Another Controller
What if you want to render a template from an entirely different controller from the one that contains the action code? You can also do that with render, which accepts the full path (relative to app/views) of the template to render. For example, if you’re running code in an AdminProductsController that lives in app/controllers/admin, you can render the results of an action to a template in app/views/products this way:
render 'products/show'
Rails knows that this view belongs to a different controller because of the embedded slash character in the string. If you want to be explicit, you can use the :template option (which was required on Rails 2.2 and earlier):