RACMulticastConnection

1创建信号

 RACSignal *signal = [RACSignal createSignal:^RACDisposable *(id<RACSubscriber> subscriber) {
    NSLog(@"发送热门模块");
    [subscriber sendNext:@"热门模块的数据"];
    return nil;
}];

2把信号转换成连接类

RACMulticastConnection *connection = [signal publish];

3订阅连接类的信号

 [connection.signal subscribeNext:^(id x) {
    NSLog(@"订阅者1%@",x);
}];

[connection.signal subscribeNext:^(id x) {
    NSLog(@"订阅者2%@",x);
}];

[connection.signal subscribeNext:^(id x) {
    NSLog(@"订阅者3%@",x);
}];

4连接

 [connection connect];