Dispatch Awesome

An overview of a few some awesome libdispatch features.

This talk was given at NSMeetup in San Francisco, California.

Transcript

1. D I S P A T C H A W E S O M E
2. Hi, I’m Sam @soffes
3. Grand Central Dispatch libdispatch
4. Open Source libdispatch.macosforge.org
5. What’s here?
6. dispatch_async dispatch_sync
7. dispatch_async(dispatch_get_main_queue(), ^{ NSLog(@"Hello world"); });
8. dispatch_after dispatch_time
9. dispatch_time_t time = dispatch_time(DISPATCH_TIME_NOW, 2.0 * NSEC_PER_SEC); dispatch_after(time, dispatch_get_main_queue(), ^{ NSLog(@"The future"); });
10. dispatch_once
11. static NSArray *stuff = nil; static dispatch_once_t onceToken; dispatch_once(&onceToken, ^{ ! stuff = @[@"NSMeetup", @"SF"]; });
12. dispatch_apply
13. dispatch_apply(10, queue, ^(size_t i) { ! NSLog(@"Iteration: %ld", i); });
14. dispatch_group
15. dispatch_queue_t queue = dispatch_get_main_queue(); dispatch_group_t group = dispatch_group_create(); dispatch_group_async(group, queue, ^{ ! NSLog(@"Hello"); }); dispatch_group_async(group, queue, ^{ ! NSLog(@"World"); }); dispatch_group_notify(group, queue, ^{ ! NSLog(@"Done!"); }); dispatch_release(group);
16. dispatch_semaphore
17. dispatch_semaphore_t s = dispatch_semaphore_create(0); dispatch_semaphore_signal(s); dispatch_async(backgroundQueue, ^{ ! dispatch_semaphore_wait(s, DISPATCH_TIME_FOREVER); ! dispatch_async(dispatch_get_main_queue(), ^{ NSLog(@"Animation is done!"); ! }); }); [UIView animateWithDuration:0.3 animations:block completion:^(BOOL finished) { // ... dispatch_semaphore_signal(s); }];
18. dispatch_suspend dispatch_resume
19. dispatch_suspend(queue); dispatch_resume(queue);
20. dispatch_*_f
21. dispatch_barrier_*
22. dispatch_io
23. dispatch_set_target_queue
24. dispatch_source dispatch_data
25. Patterns
26. Main Background Main
27. Serial Queue
28. Thanks