copyWithZone issue
I am trying to make a copy of my UIViewController subclass by doing:

    BookViewController *bookVC = [catalogFlatViewController copy];

and I have the following error:

    '-[BookViewController copyWithZone:]: unrecognized selector sent to instance 0x8e5f00'
copyWithZone issue
===

I am trying to make a copy of my UIViewController subclass by doing:

    BookViewController *bookVC = [catalogFlatViewController copy];

and I have the following error:

    '-[BookViewController copyWithZone:]: unrecognized selector sent to instance 0x8e5f00'