Type Method

allocWithZone:

Returns a new instance of the receiving class.

Declaration

+ (instancetype)allocWithZone:(struct _NSZone *)zone;

Parameters

zone

This parameter is ignored.

Return Value

A new instance of the receiver.

Discussion

The isa instance variable of the new instance is initialized to a data structure that describes the class; memory for all other instance variables is set to 0.

You must use an init... method to complete the initialization process. For example:

TheClass *newObject = [[TheClass allocWithZone:nil] init];

Do not override allocWithZone: to include any initialization code. Instead, class-specific versions of init... methods.

This method exists for historical reasons; memory zones are no longer used by Objective-C.

See Also

Creating, Copying, and Deallocating Objects

+ alloc

Returns a new instance of the receiving class.

- init

Implemented by subclasses to initialize a new object (the receiver) immediately after memory for it has been allocated.

- copy

Returns the object returned by copyWithZone:.

+ copyWithZone:

Returns the receiver.

- mutableCopy

Returns the object returned by mutableCopyWithZone: where the zone is nil.

+ mutableCopyWithZone:

Returns the receiver.

- dealloc

Deallocates the memory occupied by the receiver.

+ new

Allocates a new instance of the receiving class, sends it an init message, and returns the initialized object.