When to request access to events?

Question

I have a view controller, in which I access the eventstore.

I am not sure when in the view controller I should request permission to access?

I currently request permission in viewDidLoad.

But, what happens, if the user puts the app in the background, forgets it for a while, revokes access permission in the system settings, and finally comes back to my app. viewDidLoad is not called then...

As a best practice, shall I request permission in viewWillAppear, too?

Answer 1

I'd suggest a third alternative: Instead of viewDidLoad or viewDidAppear, I'd ask only when the app actually requires access to the event store, and not before. If you do it when the view first appears, the user's reaction might be "oh, I can't imagine why this app needs access, so I'll deny it". But if they initiate some action on their part which clearly requires access to the event store, that's a great time to ask permission, because the reaction will be "oh, of course I do."