获取通讯录中的所有群组名字

使用ABRecordCopyCompositeName()功能：
ABAddressBookRef addressBook = ABAddressBookCreateWithOptions(NULL, NULL);
if (addressBook != NULL) {
    ABAddressBookRequestAccessWithCompletion(addressBook, ^(bool granted, CFErrorRef error) {
        if (granted) {
            CFArrayRef allGroups = ABAddressBookCopyArrayOfAllGroups(addressBook);
            if (allGroups != NULL) {
                NSMutableArray *names = [NSMutableArray array];
                for (int i = 0; i < CFArrayGetCount(allGroups); i++) {
                    ABRecordRef group = CFArrayGetValueAtIndex(allGroups, i);
                    CFStringRef name = ABRecordCopyCompositeName(group);
                    [names addObject:(__bridge NSString *)name];
                    CFRelease(name);
                }
                NSLog(@"names = %@", names);
                CFRelease(allGroups);
            }
        }
        CFRelease(addressBook);
    });
}