简化通知中心的使用

 

 

说明

1. 简化通知中心，笔者曾经实现过不需要移除的通知中心，基于弱引用集合（相对于强引用集合如NSArray，NSDictionary等）编写，本例子并无太多新意

2. 简化的通知中心由一个对象组织控制，不需要你手动移除被监听的对象，这是唯一的一点点有新意的地方

3. 在处理接收通知对象的地方，笔者提供了一个方法来简化取值操作，相对应的，发送通知消息的时候，被发送的对象也请使用指定的格式（都是用weak修饰，无需担心被持有）

 

源码

////  NotificationCenterObject.h//  NotificationCenter////  Created by YouXianMing on 15/7/15.//  Copyright (c) 2015年 YouXianMing. All rights reserved.//#import 
     
      @interface PostObject : NSObject@property (nonatomic, strong) NSString *flag;@property (nonatomic, weak)   id        data;/** *  便利构造器初始化对象 * *  @param flag 识别标签 *  @param data 数据 * *  @return 实例对象 */+ (instancetype)postObjectWithFlag:(NSString *)flag data:(id)data;/** *  处理通知中心事件 * *  @param sender 通知中心的通知对象 * *  @return 实例对象 */+ (instancetype)accessNotificationCenterObject:(id)sender;@end///@interface NotificationCenterObject : NSObject/** *  === 必须先使用此方法进行初始化 === * *  初始化通知中心 * *  @param observer 观察对象 *  @param name     注册标签 *  @param selector 执行用selector * *  @return 实例对象 */+ (instancetype)withObserver:(id)observer                registerName:(NSString *)name                    selector:(SEL)selector;/** *  给指定注册标签发信息 * *  @param name     注册标签 *  @param postData 发送的对象 */+ (void)postToRegisterName:(NSString *)name data:(PostObject *)postData;@property (nonatomic, readonly, strong) NSString *name;@property (nonatomic, readonly, weak)   id        observer;/** *  移除 */- (void)remove;/** *  重新添加上 */- (void)reAdd;@end////** *  创建通知对象 * *  @param flag 标签 *  @param data 传递的数据 * *  @return 通知对象 */static inline PostObject * POST_OBJECT(NSString *flag, id data) {        return [PostObject postObjectWithFlag:flag data:data];}/** *  处理通知的对象 * *  @param sender 接收的通知对象 * *  @return 通知对象 */static inline PostObject * ACCESS_POST_OBJECT(id sender) {        return [PostObject accessNotificationCenterObject:sender];}/** *  发送通知消息 * *  @param name       指定的标签 *  @param postObject 通知的对象 * */static inline void POST_MSG_TO(NSString *name, PostObject *postObject) {    [NotificationCenterObject postToRegisterName:name data:postObject];}/** *  注册通知中心 * *  @param name     指定的标签 *  @param observer 被注册的对象 *  @param selector 执行的句柄 * *  @return 实例对象 */static inline NotificationCenterObject * REGISTER_MSG_CENTER_WITH(NSString *name, id observer, SEL selector) {        return [NotificationCenterObject withObserver:observer registerName:name selector:selector];}
     

////  NotificationCenterObject.m//  NotificationCenter////  Created by YouXianMing on 15/7/15.//  Copyright (c) 2015年 YouXianMing. All rights reserved.//#import "NotificationCenterObject.h"@implementation PostObject+ (instancetype)postObjectWithFlag:(NSString *)flag data:(id)data {    PostObject *postObject = [PostObject new];    postObject.flag        = flag;    postObject.data        = data;        return postObject;}+ (instancetype)accessNotificationCenterObject:(id)sender {    PostObject *postData = nil;        if ([sender isKindOfClass:[NSNotification class]]) {            NSNotification *notiData = sender;                if ([notiData.object isKindOfClass:[PostObject class]]) {                        postData = notiData.object;        }    }        return postData;}@end@interface NotificationCenterObject ()@property (nonatomic, strong) NSString *name;@property (nonatomic, weak)   id        observer;@property (nonatomic)         SEL       observerSelector;@property (nonatomic)         BOOL      haveAddObserver;@end@implementation NotificationCenterObject+ (void)postToRegisterName:(NSString *)name data:(PostObject *)postData {    [[NSNotificationCenter defaultCenter] postNotificationName:name object:postData];}+ (instancetype)withObserver:(id)observer registerName:(NSString *)name selector:(SEL)selector {    NotificationCenterObject *notificationCenterObject = [NotificationCenterObject new];    notificationCenterObject.name                      = name;    notificationCenterObject.observer                  = observer;    notificationCenterObject.observerSelector          = selector;        notificationCenterObject.haveAddObserver           = YES;    [[NSNotificationCenter defaultCenter] addObserver:observer selector:selector name:name object:nil];        return notificationCenterObject;}- (void)remove {    if (self.haveAddObserver == YES && _name && _observer) {        self.haveAddObserver = NO;        [[NSNotificationCenter defaultCenter] removeObserver:_observer name:_name object:nil];    }}- (void)reAdd {    if (self.haveAddObserver == NO && _name && _observer) {        self.haveAddObserver = YES;        [[NSNotificationCenter defaultCenter] addObserver:_observer selector:_observerSelector name:_name object:nil];    }}- (void)dealloc {        if (self.haveAddObserver == YES) {                NSLog(@"已经释放");        [[NSNotificationCenter defaultCenter] removeObserver:_observer name:_name object:nil];    }}@end

 

细节

用内联函数将OC风格函数简化为C风格函数，能够稍微缩短代码编写长度，其实并无实用价值，装的成分居多。