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add-observer Function

Summary

Adds an observer to a notification center.

Package

cocoa

Signature

add-observer target selector &key name object center

Arguments
target
A pointer to an Objective-C foreign object.
selector
A selector of type sel.
name
A string or nil.
object
A pointer to an Objective-C foreign object or nil.
center
A notification center.
Description

The function add-observer calls the Objective-C instance method "addObserver:selector:name:object:" of center to add target as an observer for selector with the given name and object, which both default to nil.

If center is omitted then it defaults to the default notification center.

See also

remove-observer


LispWorks Objective-C and Cocoa Interface User Guide and Reference Manual - 01 Dec 2021 19:38:33