How do you copy a CALayer?

Question

How can you make an NSArray full of multiple instances of a CALayer (all with the same frame, contents etc)?

Background: CALayer takes a bit of overhead to create, so I would like to create a number of CALayers (all sharing the same properties) in the init method of a class (to be used later on in that class.)

Answer 1

CALayer doesn't have a built in -(id)copy method. I'm not sure why. It's not difficult to gin up your own however. Create a CALayer category and write your own copy method. All you have to do is instantiate and manually get the public ivars/properties from the original and set to the new copy. Don't forget to call [super copy]

BTW, CALayer is an object. You can add it to an NSArray.

Answer 2

I haven't tried this with CALayer specifically, but I know you can perform a deep-copy by taking advantage of NSCoding:

CALayer *layer = [NSKeyedUnarchiver unarchiveObjectWithData:[NSKeyedArchiver archivedDataWithRootObject:layer]];

I'm not sure how copying them would really help with performance, though.