Name
NSDistributedNotificationCenter — Mac OS X 10.0
Synopsis
This class extends the functionality of its superclass,
NSNotificationCenter
, by providing a means of
sending notifications to objects in other tasks. Every task has a
default distributed
notification center that objects send notifications to, as well as
register
themselves as observers. To obtain your
application’s distributed notification center
object, use the factory method defaultCenter
.
To register
an object as a receiver of a specified
notification we use the method
addObserver:selector:name:object
:. The observer is
the object that wishes to be notified of the notification identified
by name
:. The argument
selector
: specifies what method should be invoked
in response to the notification. The object
:
parameter allows us to restrict the notifications the observer
responds to those posted by the specified object. To remove an
observer, invoke the method removeObserver
:, which
removes the observer for all notifications. To be selective about
what notifications from which objects to stop observing, use the
method removeObserver:name:object
:.
NSNotificationCenter
provides three methods for
posting notifications: postNotification
:,
postNotificationName:object
:, and
postNotification-Name:object:userInfo
:. Each of
these methods offers different levels of control over how the
notification is posted.
For more information about the notifications system, see Chapter 2.
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@interface NSDistributedNotificationCenter : NSNotificationCenter ... |
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