/*
* Copyright (c) 2008-2024 Jonathan Schleifer <js@nil.im>
*
* All rights reserved.
*
* This program is free software: you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License version 3.0 only,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* version 3.0 for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* version 3.0 along with this program. If not, see
* <https://www.gnu.org/licenses/>.
*/
#import "OFObject.h"
#import "OFNotification.h"
OF_ASSUME_NONNULL_BEGIN
@class OFMutableDictionary OF_GENERIC(KeyType, ObjectType);
#ifdef OF_HAVE_THREADS
@class OFMutex;
#endif
#ifdef OF_HAVE_BLOCKS
/**
* @brief A block which is called when a notification has been posted.
*
* @param notification The notification that has been posted
*/
typedef void (^OFNotificationCenterBlock)(OFNotification *notification);
#endif
/**
* @class OFNotificationCenter OFNotificationCenter.h \
* ObjFW/OFNotificationCenter.h
*
* @brief A class to send and register for notifications.
*/
#ifndef OF_NOTIFICATION_CENTER_M
OF_SUBCLASSING_RESTRICTED
#endif
@interface OFNotificationCenter: OFObject
{
#ifdef OF_HAVE_THREADS
OFMutex *_mutex;
#endif
OFMutableDictionary *_handles;
}
#ifdef OF_HAVE_CLASS_PROPERTIES
@property (class, readonly, nonatomic) OFNotificationCenter *defaultCenter;
#endif
/**
* @brief Returns the default notification center.
*/
+ (OFNotificationCenter *)defaultCenter;
/**
* @brief Adds an observer for the specified notification and object.
*
* @param observer The object that should receive notifications
* @param selector The selector to call on the observer on notifications. The
* method must take exactly one object of type
* @ref OFNotification.
* @param name The name of the notification to observe
* @param object The object that should be sending the notification, or `nil`
* if the object should be ignored to determine what
* notifications to deliver
*/
- (void)addObserver: (id)observer
selector: (SEL)selector
name: (OFNotificationName)name
object: (nullable id)object;
/**
* @brief Removes an observer. All parameters must match those used with
* @ref addObserver:selector:name:object:.
*
* @param observer The observer that was specified when adding the observer
* @param selector The selector that was specified when adding the observer
* @param name The name that was specified when adding the observer
* @param object The object that was specified when adding the observer
*/
- (void)removeObserver: (id)observer
selector: (SEL)selector
name: (OFNotificationName)name
object: (nullable id)object;
#ifdef OF_HAVE_BLOCKS
/**
* @brief Adds an observer for the specified notification and object.
*
* To remove the observer again, use @ref removeObserver:.
*
* @param name The name of the notification to observe
* @param object The object that should be sending the notification, or `nil`
* if the object should be ignored to determine what
* notifications to deliver
* @param block The block to handle notifications
* @return An opaque object to remove the observer again
*/
- (id)addObserverForName: (OFNotificationName)name
object: (nullable id)object
usingBlock: (OFNotificationCenterBlock)block;
/**
* @brief Removes an observer. The specified observer must be one returned by
* @ref addObserver:selector:name:object:.
*
* @param observer The object that was returned when adding the observer
*/
- (void)removeObserver: (id)observer;
#endif
/**
* @brief Posts the specified notification.
*
* @param notification The notification to post
*/
- (void)postNotification: (OFNotification *)notification;
/**
* @brief Posts a notification with the specified name and object.
*
* @param name The name for the notification
* @param object The object for the notification
*/
- (void)postNotificationName: (OFNotificationName)name
object: (nullable id)object;
/**
* @brief Posts a notification with the specified name, object and additional
* information.
*
* @param name The name for the notification
* @param object The object for the notification
* @param userInfo Additional information for the notification
*/
- (void)postNotificationName: (OFNotificationName)name
object: (nullable id)object
userInfo: (nullable OFDictionary *)userInfo;
@end
OF_ASSUME_NONNULL_END