ios - 应用程序在 iPhone 中的 dispatch_queue 内崩溃

Question

在我的一个应用程序中，我使用了 dispatch_queue 并在其中声明了一个 dispatch_asyc 队列来检查地址簿。现在，当编译器到达返回语句时，它会导致应用程序崩溃。下面是我的源代码。

   dispatch_queue_t queue = dispatch_queue_create("abc", NULL);

   dispatch_async(queue, ^{
       // Request authorization to Address Book
       ABAddressBookRef addressBookRef = ABAddressBookCreateWithOptions(NULL, NULL);
       if (ABAddressBookGetAuthorizationStatus() == kABAuthorizationStatusNotDetermined) {
           ABAddressBookRequestAccessWithCompletion(addressBookRef, ^(bool granted, CFErrorRef error) {
               // First time access has been granted...

               // All good.
               completionBlock?completionBlock(YES):nil;

               dispatch_async(queue, ^{
                   if (addressBookRef) {
                       CFRelease(addressBookRef);
                   };
               });

               return;
           });

Answer 1

根据documentation on Address Book , 你不能跨线程使用 ABAddressBookRef

Important: Instances of ABAddressBookRef cannot be used by multiple threads. Each thread must make its own instance by calling ABAddressBookCreate.

参见 this question有关如何执行此操作的更多想法: