022*:GCD源码底层探索 (dispatch_group_async dispatch_group_enter dispatch_group_leave) _dispatch_call_block_and_release (dx_push pthread_creat dx_invoke)dispatch_semaphore_signal wait create 问题 _dispatch_call_block_and_release执行任务 同步回调,block执行 block回调:底层通过dx_push递归,会重定向到根...
dispatch_group_t group = dispatch_group_create(); dispatch_queue_t queue = dispatch_queue_create("usedQueue", DISPATCH_QUEUE_CONCURRENT); //这里要是换成串行队列,则会按顺序执行了,并不要求顺序。 dispatch_group_async(group, queue, ^{ NSLog(@"task1"); NSLog(@"task1---%@",[NSThread cur...
iOS 4.0+iPadOS 4.0+Mac Catalyst 13.1+macOS 10.6+tvOSvisionOS 1.0+watchOS 2.0+ externvoiddispatch_group_async_f(dispatch_group_tgroup,dispatch_queue_tqueue,void*context,dispatch_function_twork); Parameters group A dispatch group to associate the submitted function with. The group is retained by th...
在 40 秒内（由 Controller Manager 的 --node-monitor-grace-period 参数指定），节点进入 NotReady ...
2.dispatch_group_enter(group); 声明dispatch_group_enter(group)此行下面的任务由group组管理,group组的任务数+1 3.dispatch_group_leave(group); 相应的任务执行完成,group组的任务数-1 4.dispatch_group_create(); 创建一个group组 5.dispatch_group_wait(group1, DISPATCH_TIME_FOREVER); ...
分别异步执行2个耗时任务,然后当2个耗时任务都执行完毕后再回到主线程执行任务。这时候可以用到 GCD 的队列组。 调用队列组的 dispatch_group_async先把任务放到队列中,然后将队列放入队列组中。或者使用队列组的 dispatch_group_enter、dispatch_group_leave组合 来实现dispatch_group_async。
dispatch_group_enter(group); dispatch_group_async(group, queue, ^{ NSLog(@"%@ start 任务2", [NSThread currentThread]); NSLog(@"%@ 任务2", [NSThread currentThread]); dispatch_group_leave(group); }); dispatch_group_enter(group); ...