[NSRunLoop.currentRunLoop run];开启runloop后可以用了 ``` - (void)viewDidLoad { [super viewDidLoad]; queue = dispatch_queue_create("asds", DISPATCH_QUEUE_CONCURRENT); dispatch_async(queue, ^{ [self performSelector:@selector(testSel:) withObject:@"asdfd" afterDelay:3]; [NSRunLoop.currentRunLoop run]; }); } - (void)testSel:(id)sender{ NSLog(@"%s=%@",__FUNCTION__,sender); } ```