Making configuration changes on user-input

Hello everyone. I tried asking in the Vuforia forums but no answer so far. I'm using an ARCamera which is using a Video See-Through Eyewear type, which has a script attached. I'm hoping to allow the user to switch between Video See-Through (used for cardboards) and None(normal AR). I can change the Eyewear's type in the Start() method using this line :

DigitalEyewearARController.Instance.SetEyewearType(DigitalEyewearARController.EyewearType.OpticalSeeThrough);

But this is only called once, when the application starts. I have another method which would be called when a button is pressed. The function is called but the camera mode doesn't change. Is it possible to achieve this ? If not, can I make a pre-start configuration menu, were the user can set the Eyerwear Type, before starting ?

Any help is appreciated. Have a great day.