Question

I have some code which runs in a timer, but I would like to have a few of these run simultaneously.

How are threads run in objective c?

Can I put the current code in a method, and just start up threads and called the method in each thread?

Answer 1

The direct answer is yes: Use NSThread
The you can do something like this:

 [NSThread detachNewThreadSelector:@selector(myThreadMethod:) toTarget:self withObject:someOptions];

This will create a new Thread and call some method you define on some object. A common pitfall is that in a thread you need to create a separate NSAutoreleasePool if you’re not using Garbage Collection. In this case above it might look like this:

- (void)myThreadMethod:(id)options
{
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

    ... // your method contents here

    [pool release];
}

However, as others pointed out already, threads should be no longer used. They were sorta replaced by NSOperations, or Blocks and GrandCentralDispatch.