Question

I have a singleton class that accumulates data until that data is written to my database (if you want to know why I’m implementing things this way, see here). After saving the data, I would like to destroy the singleton. How can I do this in ARC? Or am I being paranoid and do I need to destroy it at all?

*You might say that this is a duplicate of this question, but the accepted answer here is not specific enough to be helpful. It says “You can declare a method/function you call explicitly.” What might the code for this look like? If I can’t release the object outside a method, how can I possibly pull it off inside a method? It also says “The simplest way is to have a static C++ class hold it, then release it in its destructor.” I don’t know C++, but – can you really put a C++ class in your app code?

My singleton is implemented like so:

+(NHCFamilyStatus *)familyStatus
{
  static dispatch_once_t pred;
  static NHCFamilyStatus *familyStatusSharedObject=nil;

    dispatch_once(&pred, ^
    {
        familyStatusSharedObject = [[NHCFamilyStatus alloc] init];
    });

  return familyStatusSharedObject;
}

Answer 1

If you destroy this singleton, you’ll never be able to create it again (that’s what the dispatch_once call means).

You don’t need to destroy the singleton. By all means have a method on the singleton that removes any instance variables you no longer need, but there is no need to do anything else.