How do I use Grand Central Dispatch to kick off one asynchronous call?

Question

I want to have one call occur asynchronously, the equivalent of:

doThisInASecondThreadThenHaveThisThreadDisappear:@selector(myMethod);

What is the Grand Central Dispatch call to accomplish this? I'm new to it and I get lost with all the complex stuff with queueing. I understand things that can be achieved with that, but for this simple case (that I currently care about) I'm just lost

Answer 1

dispatch_queue_t queue = dispatch_queue_create("queueName", NULL);
dispatch_async(queue, ^(void) {
    // code to execute here
});
dispatch_release(queue);

Or if you need to use the main thread:

dispatch_async(dispatch_get_main_queue(), ^(void) {
        // code to execute here
});

Answer 2

Here's a quick code example

dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_LOW, 0);    
dispatch_async(queue, ^{   
    // Stuff to do on another thread
    // Mostly heavy calculations

    dispatch_async(dispatch_get_main_queue(), ^{
        // Stuff to do on main thread
        // Mostly UI stuff
    });                    
});