Question

I want to write an App, that can run two different “threads”, one for a Server one for a Client. I have heard, that in Objective-C Dispatch Queues and Blocks are the way to go. I have read the Apple Documentation about Blocks and Dispatch Queues to quite a large extend, however I still fail at the very beginning of my coding.

Am I right, that I need to create 2 Blocks, one for my server code and one for my client code and then put those blocks in the dispatch queue to run concurrently?

I was now trying to create a block for my server, and failed miserably. I tried the following:

#import <Foundation/Foundation.h>

@interface Server : NSObject {
    void (^server)(NSString*, int);
}

@end

And then

 #import "Server.h"

@implementation Server
   server = ^(NSString* host, int port) {
};

@end

I thought I would have to declare the block variable first in a header file, so that I can later refer to it in my ViewController. Any answers about the general structure with some code examples would be highly appreciated 🙂

Answer 1

I would advise creating a typedef, so you can easily create blocks of that type. Like this:

typedef void (^ServerBlock)(NSString *host, int port);

On your .h:

ServerBlock myServerBlock;

On your .m:

myServerBlock = ^(NSString* host, int port) {};

You can put your typedef inside a .h file called constants and then import it on your .pch file (this is just suggestion…)