In the Slicer Custom Application Template, ViewControllers module is disabled by default, so you either need to initialize the view defaults yourself or enable the module.
I’ve submitted a pull request to not disable this module by default:
In the Slicer Custom Application Template, ViewControllers module is disabled by default, so you either need to initialize the view defaults yourself or enable the module.
I’ve submitted a pull request to not disable this module by default: