Using selected NSManagedObject across different controllers
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I have an entity called Practice and I use a View Controller called SelectorViewController to select one of the practices, selectedPractice. I then return selectedPractice to a view Controller called RegularViewController where I display some of the selectedPractice attributes. All of this works fine. However the app has a number of other View Controllers which can be reached by modal segues from instances of RegularViewController. As a result, if I leave and then come back to RegularViewController, selectedPractice is reset as null. I would also like to save selectedPractice so that it is available at app initialisation if it has previously been set in SelectorViewController. How do I achieve this by making selectedPractice persistent across the app, and available at runtime?

Regards  