How to set the current template from the controller level

[sgweb]

How to set the current template from the controller level

[nWidart]

Do you mean theme? If so you can use the stylist package and its classes to set the theme.
For some inspiration look at the authentication routes, which if I remember correctly set the theme via the controller.

[sgweb]

I created a flatly based theme, wanted to choose the right theme in the controller for the user

[nWidart]

As I explained check the authentication controller for this.