iOS 通用代理的写法 一个代理添加多个执行函数

/*添加代理，当不使用时记得移除*/- (void)addDelegate:(id<HXFriendRelationManagerDelegate>)delegate {    @synchronized (self.delegates) {        if (![self.delegates containsObject:delegate]) {            [self.delegates addObject:delegate];        }    }}//移除代理- (void)removeDelegate:(id<HXFriendRelationManagerDelegate>)delegate {    @synchronized (self.delegates) {        [self.delegates removeObject:delegate];    }}

//代理的执行

- (void)notFriendListChange {    @synchronized (self.delegates) {                dispatch_async(dispatch_get_main_queue(), ^{            for (id<HXFriendRelationManagerDelegate> delegate in self.delegates) {                if ([delegate respondsToSelector:@selector(hxFriendListChange)]) {                    [delegate performSelector:@selector(hxFriendListChange)];                }            }          });    }}//代理的执行- (void)notADDFriendMsg:(EMMessage *)msg {        @synchronized (self.delegates) {        for (id<HXFriendRelationManagerDelegate> delegate in self.delegates) {            if ([delegate respondsToSelector:@selector(getAddFriendMessage:)]) {                [delegate performSelector:@selector(getAddFriendMessage:)withObject:msg];            }        }    }    }