Type Alias

CFBagRetainCallBack

Prototype of a callback function used to retain a value being added to a bag.

Declaration

typedef const void *(*CFBagRetainCallBack)(CFAllocatorRef allocator, const void *value);

Parameters

allocator

The bag’s allocator.

value

The value being added to the bag.

Return Value

The value to store in the bag, which is usually the value parameter passed to this callback, but may be a different value if a different value should be stored in the collection.

Discussion

This callback is passed to CFBagCreate in a CFBagCallBacks structure.

See Also

Callbacks

CFBagApplierFunction

Prototype of a callback function that may be applied to every value in a bag.

CFBagCopyDescriptionCallBack

Prototype of a callback function used to get a description of a value in a bag.

CFBagEqualCallBack

Prototype of a callback function used to determine if two values in a bag are equal.

CFBagHashCallBack

Prototype of a callback function invoked to compute a hash code for a value. Hash codes are used when values are accessed, added, or removed from a collection.

CFBagReleaseCallBack

Prototype of a callback function used to release a value before it’s removed from a bag.

Beta Software

This documentation contains preliminary information about an API or technology in development. This information is subject to change, and software implemented according to this documentation should be tested with final operating system software.

Learn more about using Apple's beta software