allocWithZone:

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
• init()
• copy()
• copyWithZone:
• mutableCopy()
• mutableCopyWithZone:
• dealloc
• new