2

我正在尝试连接到自定义 GCD 队列中的服务器。我就是这样做的。

- (void) initNetworkCommunication{
    if(!self.connQueue){
        self.connQueue = dispatch_queue_create("connection_queue", NULL);
    }

    dispatch_async(self.connQueue, ^(void) {
        if(self.inputStream ==nil && self.outputStream ==nil) {
            CFReadStreamRef readStream;
            CFWriteStreamRef writeStream;
            NSString *host= [[NSUserDefaults standardUserDefaults] objectForKey:@"ip_preference"];
            NSNumber *portNum = [[NSUserDefaults standardUserDefaults] objectForKey:@"port_preference"];

            int port = [portNum intValue];
            CFStreamCreatePairWithSocketToHost(NULL, (__bridge CFStringRef)host, port, &readStream, &writeStream);

            CFReadStreamSetProperty(readStream, kCFStreamNetworkServiceType, kCFStreamNetworkServiceTypeVoIP);
            CFWriteStreamSetProperty(writeStream, kCFStreamNetworkServiceType, kCFStreamNetworkServiceTypeVoIP);  

            self.inputStream = (__bridge NSInputStream *)readStream;
            self.outputStream = (__bridge NSOutputStream *)writeStream;
            [self.inputStream setDelegate:self];
            [self.outputStream setDelegate:self];

            [self.inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSRunLoopCommonModes];
            [self.outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSRunLoopCommonModes];

            [self.outputStream open];
            [self.inputStream open];
        } else {
            NSLog(@"persistant connection alerady opened");
            return;
        }
    });
}

现在,如果我在 dispatch_sync 中编写这段代码,它会正确调用委托函数。

- (void)stream:(NSStream *)theStream handleEvent:(NSStreamEvent)streamEvent

但是,当我使用我想要做的 dispatch_asynch 时,它不会调用我的委托函数。

从到目前为止我所读到的内容来看,GCD 队列有一个与之关联的运行循环,但这些不是由系统运行的,我们需要自己这样做。我在理论上理解这一点,但它是如何完成的。以某种方式与此相关的调度源?

先感谢您。

4

2 回答 2

7

后添加此方法[self.inputStream open];

[[NSRunLoop currentRunLoop]run];

这使接收器进入一个永久循环,在此期间它处理来自所有附加输入源的数据。查看有关RunLoops 的苹果文档

于 2012-12-24T13:42:08.307 回答
1

另一种方式让dispatch_get_main_queue使用时继续运行dispatch_async();

于 2015-01-05T02:49:25.560 回答