gistfile1.m

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];

	if (dispatch_queue_create != NULL) {
		main_queue = dispatch_get_main_queue();
		timeline_queue = dispatch_queue_create("com.ey-office.gcd-sample.timeline", NULL);
		image_queue = dispatch_queue_create("com.ey-office.gcd-sample.image", NULL);

		dispatch_async(timeline_queue, ^{
			[self getPublicTimeline];
			dispatch_async(main_queue, ^{
				[self.tableView reloadData];
			});
		});
	} else {
		[self getPublicTimeline];
		[self.tableView reloadData];
	}
}