When should I use retainCount?
You should never use -retainCount , because it never tells you anything useful. The implementation of the Foundation and AppKit/UIKit frameworks is opaque; you don’t know what’s being retained, why it’s being retained, who’s retaining it, when it was retained, and so on.
What is CFTypeRef?
Discussion. The CFTypeRef type is the base type defined in Core Foundation. It is used as the type and return value in several polymorphic functions. It is a generic object reference that acts as a placeholder for other true Core Foundation objects.
What is swift Retain count?
Retain Count represents number of owners for a particular object. It is zero till object does not have any owners. Increase in one ownership claim will cause retain count to increase by 1 and decrease will cause it to decrement by 1. Example: – Class A object is created using alloc/init and retain count is 1.
What does a retain count represents in ARC?
As the name implies, Automatic Reference Counting keeps count of the number of references to a class instance. It does this to understand when it is safe to dispose of a class instance. We can store another reference to the Device instance we created in the deviceJane variable.
How do I print a retain count in Swift?
You can do this by putting break points or using print(CFGetRetainCount(CFTypeRef!)) function in your code . You can also increment the reference count of an Object using the CFRetain function, and decrement the reference count using the CFRelease function.
What happens when you call retain on an object?
That means that you have no control over it’s lifetime. To make sure that it doesn’t get released before you are done with it, you call retain on the object. You now own this object and are responsible for calling release on it at some time in the future.
How does ARC work Swift?
Swift uses Automatic Reference Counting (ARC) to track and manage your app’s memory usage. ARC automatically frees up the memory used by class instances when those instances are no longer needed.
What is ARC Xcode?