28

不确定行为,因为我怀疑我遇到了僵局,

我有一个包含多个对象的类 - 每个对象创建一个同名的队列。我不确定 GCD 是否在对象之间重用相同的队列,或者它们是否只是共享相同的名称。

例如

@interface MyClass

-(void)doSomeWork
@property (nonatomic,strong) dispatch_queue_t myQueue;

@end

@implementation MyClass

-(id)init
{
  self = [super init];
  self.myQueue = dispatch_queue_create("MyQueue",DISPATCH_QUEUE_SERIAL);
  return self;
}

-(void)doSomeWork
{
  dispatch_async(self.myQueue,^{
    // some long running work
  });
}

@end


@interface SomeClassWhichCreatesALotOfObjects

@end


@implementation SomeClassWhichCreatesALotOfObjects

-(void)someMethod
{
  for(int i = 0; i < 10000; i++)
  {
    MyClass *object = [MyClass new];
    [object doSomeWork]; // are these running in serial to each other or are each offset to the queue their object has created? Can't understand from the debugger
  }
}
@end
4

2 回答 2

43

正如 Apple 的文档所述,标签是:

附加到队列的字符串标签,以在调试工具(如 Instruments...

它被用作提示,仅此而已。

编辑

这是使用共享队列所需的代码。

+ (dispatch_queue_t)sharedQueue
{
    static dispatch_queue_t sharedQueue;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        sharedQueue = dispatch_queue_create("MyQueue", NULL);
    });
    return sharedQueue;
}
于 2013-10-17T08:15:45.823 回答
16

dispatch_queue_create顾名思义,它创建了一个调度队列。你给它的标签不需要是唯一的,它只是用于调试目的。

于 2013-10-17T08:16:22.077 回答